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2017

ICME 2017doi:The origin of most materials properties is rooted in the atomic scale. A detailed microscopic understanding of the physics and chemistry is thus mandatory for successful computational materials engineering. The MedeA computational environment provides a very efficient tool to perform atomistic...
2015

CIO Reviewdoi:Despite the downturn and reduced traction in export market, the U.S. chemical industry is fast picking pace. The chemical sector is now spiraling towards a sustained global expansion that will result in increased trade. This year, the maximum traction in chemical was observed in the automotive...

ApplCatA, 2015 vol. 495 pp. 115123.Acrylonitrile is a major chemical intermediate used in the production of a wide range of chemical and polymer products. Central to the commercial process is a proprietary catalyst consisting of a complex mixture of metal oxides containing a bismuthcontaining molybdate phase that is active and...

Journal of Nuclear Materials 460: 82–96.(2015)Diffusion of point defects, nucleation of dislocation loops, and the associated dimensional changes of pure and Hloaded hcpZr have been investigated by a combination of ab initio calculations and classical simulations. Vacancy diffusion is computed to be anisotropic with Dvac,basal = 8.6
2014

Journal of Nuclear Materials 445, no. 1: 241–250. (2014)The effect of the alloying elements Sn, Fe, Cr, Ni, Nb, and O on hydrogencontaining alphazirconium and zirconium hydrides is investigated using ab initio quantum mechanical calculations and classical simulations. Cr, Fe, and Ni atoms attract interstitially dissolved H atoms whereas interstitial...

J. Phys. Chem. C, 118 (13), 6934 (2014)doi: 10.1021/jp501538vThis work examines the complex nature of SOₓ (x = 0–4) interaction and oxidation on Pt(111) and Pd(111) surfaces using density functional theory (DFT) calculations coupled with microkinetic modeling. Thermodynamic and kinetic analyses suggest similar adsorption and oxidation behaviors for SOx...

15th International Conference on Thermal, Mechanical and MultiPhysics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE), 2014Results of atomicscale simulations are presented including thermal conductivity, elastic moduli, diffusion, and adhesion. These types of simulations are most conveniently performed with the MedeA computational environment, which comprises experimental structure databases together with building...

J Chem Eng Data, 2014 p. 140603143218005.The atomistic and molecular simulation environment [MedeA](/medea) in its functionalities and graphical user interface has been enhanced to prepare and submit on the order of 1000 simulations on different structures, and to collect and help in the analysis of the results. We illustrate this with...

Modelling Simul. Mater. Sci. Eng. 22, 075009 (2014)This work shows a straightforward procedure to derive forcefields (FFs) which are able to describe the structural, thermal and transport properties of condensed phases. The approach is based on ab initio molecular dynamics trajectories and an empirical calibration such as the melting point. This is...

Materials Science & Engineering A 618 (2014) 398405Smaller grain sizes are known to improve the strength and ductility of metals by the Hall–Petch effect. Consequently, metallic thin films and structures which must sustain mechanical loads in service are deposited under processing conditions that lead to a fine grain size. In this study, we reveal...

Modelling and Simulation in Materials Science and Engineering, 2014 vol. 22 (8) p. 085012.doi:Anisotropy and temperature dependence of structural, thermodynamic and elastic properties of crystalline cellulose Iβ were computed with firstprinciples density functional theory (DFT) and a semiempirical correction for van der Waals interactions. Specifically, we report the computed temperature...

Oil Gas Sci. Technol. – Rev. IFP Energies nouvelles Dec (2014)doi: 10.2516/ogst/2014041This work demonstrates the systematic prediction of thermodynamic properties for batches of thousands of molecules using automated procedures.
2013

Journal of Applied Physics, 113(2), 023706–023706–7.(2013)doi: 10.1063/1.4774078The lattice parameter of cubic chemical vapor deposited (CVD) ZnS with measured oxygen concentrations <0.6 at. % and hydrogen impurities of <0.015 at. % has been measured and found to vary between −0.10% and +0.09% relative to the reference lattice parameter (5.4093 Å) of oxygenfree cubic...

Journal of Physics: Condensed Matter, 25(7), 075402 (2013)V is the only element in the periodic table that forms a complete solid solution with Cr and thus is particularly important in alloying strategy to ductilize Cr. This study combines firstprinciples density functional theory calculations and experiments to investigate the phase stability and...

Oil & Gas Science and Technology – Revue d’IFP Energies Nouvelles.doi: 10.2516/ogst/2012042We use periodic Density Functional Theory (DFT) method to generate the electrostatic potentials of adsorption materials and use them in Grand Canonical Monte Carlo simulations of fluid adsorption isotherms. This permits us to consider complex solids showing defects and without a priori knowledge of...

Journal of Applied Physics 114, no. 3: 033533. (2013)doi: 10.1063/1.4816094The formation of Ni(Pt)silicides on a Si(001) surface is investigated using an ab initio approach. After deposition of a Ni overlayer alloyed with Pt, the calculations reveal fast diffusion of Ni atoms into the Si lattice, which leads initially to the formation of Ni₂Si. At the same time, Si atoms...

Nature Communications 4, 2800 (2013)doi: 10.1038/ncomms3800One of the key steps in nanotechnology is our ability to engineer and fabricate lowdimensional nanoobjects, such as quantum dots, nanowires, twodimensional atomic layers or threedimensional nanoporous systems. Here we report evidence of nanotunnel opening within the subsurface region of a wide...

Mol. Sim. 39, 1165 (2013)This paper illustrates the use of Monte Carlo (MC) simulations to study a wide range of systems of interest for biomass conversion into highadded value chemicals and biofuels. The interest is focused on the use of molecular simulation to predict the physical–chemical properties of pure compounds...

Oil & Gas Science and Technology – Revue d’IFP Energies Nouvellesdoi: 10.2516/ogst/2013134Molecular Simulation of Adsorption in Microporous Materials — The development of industrial software, the decreasing cost of computing time, and the availability of welltested forcefields make molecular simulation increasingly attractive for chemical engineers. We present here several applications...

Journal of Chemical Physics 139, 214707 (2013)doi: 10.1063/1.4837697A dynamically biased (d) precursor mediated microcanonical trapping (PMMT) model of the ac tivated dissociative chemisorption of methane on Pt(111) is applied to a wide range of dissociative sticking experiments, and, by detailed balance, to the methane product state distributions from the...
2012

N. Iwamoto et al. (eds.), Molecular Modeling and Multiscaling Issues for Electronic Material Applications, Springer 2012The prediction of materials properties using atomicscale simulations offers exciting and unprecedented opportunities to expand the capabilities of electronic devices, to create novel systems, and to improve their reliability. This contribution discusses the current state of atomicscale...

Journal of Catalysis 289, no. C (May 1, 2012): 227–237The site occupancy of the various oxidation state of palladium supported on mesostructured porous aluminosilica of AlMCM41 type was studied combining density functional theory (DFT), FTIR, and Raman investigations. The study focuses on the usual +2 oxidation state highly dispersed during...

Physical Chemistry Chemical Physics 14, no. 10 (2012): 3369.doi: 10.1039/c2cp23370cThe initial step for silicate and aluminosilicate condensation is studied in water in the presence of a realistic tetrapropylammonium template under basic conditions. The model corresponds to the synthesis conditions of ZSM5. The free energy profile for the dimer formation ((OH)₃Si–O–Si–(OH)₂O⁻ or...

Journal of the American Chemical Society 134, no. 15 (April 18, 2012): 6767–6775.doi: 10.1021/ja3008566The determination of the nature and structure of surface sites after chemical modification of large surface area oxides such as silica is a key point for many applications and challenging from a spectroscopic point of view. This has been, for instance, a longstanding problem for silica reacted...

Journal of the American Chemical Society 134, no. 37: 15476–15487.doi: 10.1021/ja305366rThe mechanism of Li⁺ transport through the solid electrolyte interphase (SEI), a passivating film on electrode surfaces, has never been clearly elucidated despite its overwhelming importance to Liion battery operation and lifetime. The present paper develops a multiscale theoretical methodology to...

Thermodynamic and mechanical properties of lanthanum–magnesium phases from density functional theoryJournal of Alloys and Compounds, 512(1), 296–310 (2012)Thermodynamic and mechanical properties of the six known phases in the La–Mg phase diagram, viz. LaMg, LaMg₂, LaMg₃, La₅Mg₄₁, La₂Mg₁₇, and LaMg₁₂, and their elemental antecedents, Mg and La, are computed with density functional theory (DFT) using the PBE and PBEsol exchangecorrelation functionals...

Physical Review B. 86 (1) 014107 (2012)We discuss the structural details and the ordering of hydrogen in LaHx for 2⩽x⩽3. To this end, we combine firstprinciples calculations with the clusterexpansion method. This approach allows us to follow the H occupation of the interstitial sites within the facecentered cubic matrix of La atoms....

Journal of Materials Science, 47(21), 7542–7548 (2012)We implement DFT calculations by a Hubbardlike correction for localized strongly correlated electrons, coupled with a generalized gradient approximation to the exchangecorrelation functional to elucidate the role of the ceria based catalytically active supports for the chemical reactions...
2011

Phys. Rev. B 83, 224104 (2011)An anomalous energy pathway with energetically equivalent double saddle points for vacancy mediated selfdiffusion within an hcpTi basal plane is unveiled by density functional theory. Examination of migration pathway and phonon force constants suggests that the migrating atom tries to follow the...

Phys. Rev. Lett. 107, 016401 (2011)New calculations for vanadium dioxide, one of the most controversially discussed materials for decades, reveal that band theory as based on density functional theory is well capable of correctly describing the electronic and magnetic properties of the metallic as well as both the insulating M1 and...

The Journal of Physical Chemistry C 115, no. 39 (October 6, 2011): 19394–19404.doi: 10.1021/jp204059qExtension of the absorption properties of TiO₂ photocatalytic materials to the visible part of the solar spectrum is of major importance for energy and cleaning up applications. We carry out a systematic study of the Ndoped anatase TiO₂ material using spinpolarized density functional theory (DFT...

Chemistry  A European Journal 17, no. 44 (September 27, 2011): 12302–12309.KSi silicide can absorb hydrogen to directly form the ternary KSiH₃ hydride. The full structure of αKSiD₃, which has been solved by using neutron powder diffraction (NPD), shows an unusually short SiD lengths of 1.47 Å. Through a combination of density functional theory (DFT) calculations and...

J. Chem. Phys. 134, 024116 (2011)doi: 10.1063/1.3524336We introduce the hybrid functional HSEsol. It is based on PBEsol, a revised Perdew–Burke–Ernzerhof functional, designed to yield accurate equilibrium properties for solids and their surfaces. We present lattice constants, bulk moduli, atomization energies, heats of formation, and band gaps for...

International Journal of Hydrogen Energy, vol 36(17), pp 1073710747The interaction energies (IEs) of H₂ and various organic ligands have been computed using coupledcluster method with singles, doubles, and noniterative triples (CCSD(T)) at the complete basis set (CBS) limit. The density fittingdensity functional theorysymmetry adapted perturbation theory (DF...

J. Phys. Condens. Matter 23 (2011) 116003We present results from an electronic structure investigation of the chromium halides CrCl₃, CrBr₃, and CrI₃, as obtained by the linearized augmented plane wave method of density functional theory. Our interest focuses on the chloride. While all three halides display strong ferromagnetic coupling...

Journal of Solid State Chemistry 184, no. 4 (April 1, 2011): 797–804The crystallographic and electronic structures of compounds related to parkerite (Bi₂Ni₃S₂) are investigated with respect to the recently reported occurrence (Bi₂Pd₃Se₂) and absence (Bi₂Pd₃S₂) of superconductivity. Similarities and differences of the crystal structures are discussed within the...

Physical Chemistry Chemical Physics 13, no. 35 (2011): 15955.doi:The process of grafting H₃PMo₁₂O₄₀ onto silica surfaces is studied using periodic density functional theory methods. For surfaces with a high hydroxyl coverage, the hydroxyl groups are consumed by the polyoxometalate protons, resulting in water formation and the creation of a covalent bond between...

Ukr. J. Phys. 2011. Vol. 56, No. 8 56 (2011): 763.doi:The recombination of laserdissociated iodine molecules dissolved in CCl₄ is explored by timeresolved xray diffraction. The xray pulses employed in our experiments were generated by the ESRF synchrotron in Grenoble. The solvent contribution to the mea sured signals was eliminated using...

L'actualité chimique 353354: 66 (2011)doi:La modélisation moléculaire permet aujourd'hui de simuler les matériaux ou les fluides à l'échelle du nanomètre, voire de l'ångström, en s'appuyant sur les lois les plus fondamentales de la mécanique quantique ou de la mécanique statistique. Cette discipline de la chimie...

Fluid Phase Equilibria 304, 21 (2011)In the present work, we report isothermal vapour–liquid equilibrium data for two binarysystems: nitrogen–sulphur dioxide and oxygen–sulphur dioxide at four temperatures (323.15, 343.15, 373.15, and 413.15 K) and pressures up to 85 MPa. These data were simultaneously obtained from experimental...

Physical Review B, 84(9), 094122Results from firstprinciples investigations of the energetical, structural, electronic, and vibrational properties of model structures probing the metalrich region of the lanthanumhydrogen system, i.e., the region of the solid solution of hydrogen in lanthanum, are presented. We have studied the...

Materials Science Forum, 690, 15–18 (2011)Lattice parameters, electronic and vibrational energies, enthalpies of formation at 0 and 298 K, the elasticity tensor components, Cij, polycrystalline bulk, shear and Young’s moduli based on the Hill criteria were computed for LaMg, LaMg₂, LaMg₃, La₅Mg₄₁, La₂Mg₁₇, and LaMg₁₂. The quasiharmonic...

Journal of Membrane Science 375, 96–103 (2011)Atomic modeling was conducted to investigate the origin of S interactions with Pd alloy H selective membrane candidates selected from the Pd–Cu, Pd–Ag, and Pd–Au binary systems, as well as their constitutive metals. The electronic characteristics of these alloy/metal systems played a more...

Acta Materialia 59, 3214–3228 (2011)Diffusion in dilute Mg–X alloys, where X denotes Al, Zn, Sn and Ca impurities, was investigated with firstprinciples density functional theory in the local density approximation. Impurity diffusion coefficients were computed as a function of temperature using the 8frequency model which provided...

The Journal of Physical Chemistry Letters, 2(2), 67–72 (2011)doi: 10.1021/jz1015789The increase in oxygen binding energy was previously proposed to account for the lower oxygen reduction activity of a Pt monolayer supported on Au(111) single crystal than that on Pd(111) and pure Pt(111) surfaces. This singlecrystal based understanding, however, cannot explain the new finding of...

Nano Letters, 11(9), 3714–3719 (2011)doi: 10.1021/nl2017459We determined the sizedependent specific and mass activities of the oxygen reduction in HClO4 solutions on the Pt particles in the range of 1–5 nm. The maximal mass activity at 2.2 nm is well explained based on density functional theory calculations performed on fully relaxed nanoparticles. The...

Journal of Chemical Theory and Computation, 7(4), 1090–1101 (2011)doi: 10.1021/ct1005505An efficient procedure for normalmode analysis of extended systems, such as zeolites, is developed and illustrated for the physisorption and chemisorption of noctane and isobutene in HZSM22 and HFAU using periodic DFT calculations employing the Vienna Ab Initio Simulation Package....

Towards Crystal Structure Prediction of Complex Organic Compounds  a Report on the Fifth Blind TestActa Cryst (2011). B67, 535551Following on from the success of the previous crystal structure prediction blind tests (CSP1999, CSP2001, CSP2004 and CSP2007), a fifth such collaborative project (CSP2010) was organized at the Cambridge Crystallographic Data Centre. A range of methodologies was used by the participating groups in...

Journal of Materials 63, no. 11: 24–32. (2011)A multiscale, computational design approach for aluminum sheet alloys, which includes key inputs from the electronic, atomistic, microstructural, and continuum length scales, is re viewed within the context of room and elevated temperature forming. Specific examples, which are aimed at improv...
2010

Applied Physics Letters 96(10), 3502 (2010)doi: 10.1063/1.3353993Effective work function (EWF) changes of TiN/HfO₂ annealed at low temperatures in different ambient environments are correlated with the atomic concentration of oxygen in the TiN near the metal/dielectric interface. EWF increases of 550 meV are achieved with anneals that incorporate oxygen...

Intermetallics 18(4), 417 (2010)The deleterious lowtemperature tetragonal phases in prototypical Ptbased superalloys have variously been reported as taking the tI16U₃Si (DOc), tI16Ir₃Si (DOc′) and tP16Pt₃Ga structuretypes in contrast to the hightemperature cubic cP4Cu₃Au (L12) phase. We have investigated the relative...

Chem. Phys. Chem. 11, 105 (2010)Local structure resolved: The debated nature of Brønsted acid sites on amorphous silicaalumina is investigated by DFT calculations. Bridging Si(OH)Al and pseudobridging silanols, in throughspace interaction with Al<sub>IV</sub> or Si<sub>IV</sub>, are deprotonated by...

J. Electrochem. Soc. 157(5), A558 (2010)doi: 10.1149/1.3327913Density functional theory (DFT) is used to reveal that the polycrystalline Young’s modulus ͑ E of graphite triples as it is lithiated to LiC<sub>6</sub>. This behavior is captured in a linear relationship between E and lithium concentration suitable for continuumscale models aimed at...

Journal of Physics: Condensed Matter vol. 22 (38) pp. 384215 (2010)Computational materials science based on ab initio calculations has become an important partner to experiment. This is demonstrated here for the effect of impurities and alloying elements on the strength of a Zr twist grain boundary, the dissociative adsorption and diffusion of iodine on a...

Computational Materials Science 50, no. 2: 301–307. (2010)Selfdiffusion coefficients for hcp Mg and Zn have been calculated from firstprinciples as a function of temperature, within the generalized gradient and local density approximations. The climbing image nudged elastic band (CINEB) method has been used to provide minimum energy pathways and...

Applied Physics Letters 97, 162903 (2010)doi: 10.1063/1.3500821We demonstrate that interfacial SiO₂, usually formed during highk oxide growth on silicon using ozone (O₃), is suppressed during Al₂O₃ atomic layer deposition (ALD) by decreasing the O₃ flow rate. Firstprinciples calculations indicate that oxygen introduced by the first lowdose O₃ exposure is...

Ann. Phys. (2010) vol. 1 pp. 8In this paper we have applied firstprinciple densityfunctional theory to calculate some of the interesting roles played by vacancies in material properties, such as magnetic properties and complex formation. We use as examples our recent results on vacancies in group IIIV semiconductors like GaN...

Nature Mater. 9, 741–744 (2010)doi: 10.1038/NMAT2806Kohn–Sham density functional theory is the workhorse computational method in materials and surface science. Unfortunately, most semilocal density functionals predict surfaces to be more stable than they are experimentally. Naively, we would expect that consequently adsorption energies on surfaces...

Acta Mater. 58, 4332 (2010)The gamma surfaces in the pyramidal I {1 −1 0 1} and II {1 1−2 2} planes for hexagonal close packed Mg have been calculated using two embeddedatommethod potentials and by ab initio methods, and reasonable agreement is obtained for key stacking fault energies. Screw and edge 〈c + a〉 dislocation...

J. Phys.: Condens. Matter 22 384205 (2010)During the last 20 years computer simulations based on a quantummechanical description of the interactions between electrons and atomic nuclei have developed an increasingly important impact on materials science, not only in promoting a deeper understanding of the fundamental physical phenomena,...

Phys. Rev. B 81, 115126 (2010)We present lattice constants, bulk moduli, and atomization energies of solids using the correlation energy evaluated within the adiabatic connection fluctuationdissipation framework and applying the randomphase approximation. Recently, we have shown [_Phys. Rev. Lett._ 103 056401 (2009)] that...

Physical Review B, 82(2), 024110Systematic properties of the AGaH₄ alkali gallium hydrides (A=Li, Na, K, Rb, and Cs) are investigated within density functional theory. Seven groundstate crystal structures are identified, with two energetically indistinguishable structures found for both LiGaH₄, whose structure is as yet...

Nature Materials 9, 750 (2010)doi: 10.1038/nmat2813Despite significant advances in computational materials science, a quantitative, parameterfree prediction of the mechanical properties of alloys has been difficult to achieve from first principles. Here, we present a new analytic theory that, with input from firstprinciples calculations, is able...

Journal of Nuclear Materials 404, no. 2: 121–127. (2010)Effects of twenty impurity and alloy elements on the strength of a Zr(0001)/Zr(0001) Σ7 twist grain boundary were studied using a firstprinciples density functional approach. A ranking in the order of most weakening to most strengthening was: Cs, I, He, Te, Sb, Li, O, Sn, Cd, H, Si, C...
2009

Proceedings of Top Fuel 2009, paper 2165doi:Effects of twenty impurity and alloy elements on the strength of a Zr(0001)/Zr(0001) Σ7 twist grain boundary were studied using a firstprinciples density functional approach. A ranking in the order of most weakening to most strengthening was: Cs, I, He, Te, Sb, Li, O, Sn, Cd, H, Si, C, N, B, U, Ni...

Oil & Gas Sci. Tech. Rev. IFP 64, 707 (2009)doi: 10.2516/ogst/2009004This paper reports an overview of recent DFT studies on the atomic scale characterization of Co(Ni)MoS active phases used in selective hydrodesulfurization (HDS) catalysis. A peculiar attention is paid to the effect of the sulforeductive reaction conditions on the stability and nature of the...

J. Phys.: Condens. MatterElasticity tensor components, Cij, the crystallographic dependence of Poisson’s ratio, the phase stability, and vibrational spectra are computed for nonmagnetic and magnetic CeMg (1:1 Ce:Mg) structures using density functional theory. Results from both the generalized gradient approximation (GGA),...

Phys. Rev. Lett. 103, 056401 (2009)The adiabaticconnection fluctuationdissipation theorem suggests that the correlation energy in the random phase approximation is a suitable complement to exact exchange. We show that lattice constants, bulk moduli, and atomization energies of solids evaluated using this approximation are in very...

Phys. Rev. B 80, 134119 (2009)We use a combination of density functional theory and calorimetric measurements to investigate the monoclinic to tetragonal transition in hafnia and zirconia. We measure the transition enthalpies to be 8.4±0.7 kJ/mol in hafnia and, as previously reported, 5.272±0.544 kJ/mol in zirconia. Calculated...

Physical Review Letters, 102(7), 073005 (2009)We present a parameterfree method for an accurate determination of longrange van der Waals interactions from meanfield electronic structure calculations. Our method relies on the summation of interatomic C6 coefficients, derived from the electron density of a molecule or solid and accurate...
2008

Journal of Physics: Condensed Matter 20, 064243 (2008)A workshop, ‘Theory Meets Industry’, was held on 12–14 June 2007 in Vienna, Austria, attended by a well balanced number of academic and industrial scientists from America, Europe, and Japan. The focus was on advances in ab initio solid state calculations and their practical use in industry. The...

Physical Review B Condensed Matter 77, 134305 (2008)The temperaturedependent diffusion coefﬁcients of interstitial hydrogen, deuterium, and tritium in nickel are computed using transition state theory. The coefﬁcient of thermal expansion, the enthalpy and entropy of activation, and the preexponential factor of the diffusion coefﬁcient are obtained...

Physical Review B Condensed Matter 78, 121201 (2008)We have calculated static and dynamic response properties for several semiconducting and insulating solids using hybrid functionals, which admix a small fraction of nonlocal Fock exchange to an otherwise semilocal density functional. The calculated static and dynamic properties are clearly improved...

Journal of Computational Chemistry 29(13), 20442078 (2008)doi: 10.1002/jcc.21057During the past decade, computer simulations based on a quantummechanical description of the interactions between electrons and between electrons and atomic nuclei have developed an increasingly important impact on solidstate physics and chemistry and on materials science—promoting not only a...

Journal of Physics: Condensed Matter 20(6), 064229 (2008)Solid state systems for hydrogen storage continue to be the focus of considerable international research, driven to a large extent by technological demands, especially for mobile applications. Density functional theory (DFT) has become a valuable tool in this effort. It has greatly expanded our...

Physical Review B Condensed Matter 77, 144301 (2008)Skutterudite based materials are important for thermoelectric applications. In order to be able to tune the thermoelectric properties, it is necessary to understand the mechanism of thermal conductivity, which, in turn, is strongly inﬂuenced by the lattice dynamics. The lattice dynamics of the...

Journal of Physics: Condensed Matter 20, 064201 (2008)We present an overview of the description of structural, thermochemical, and electronic properties of extended systems using several well known hybrid Hartree–Fock/densityfunctionaltheory functionals (PBE0, HSE03, and B3LYP). In addition we address a few aspects of the evaluation of the Hartree–...

Physical Review B Condensed Matter 78(10), 104116 (2008)The structural, electronic, and phonon properties of the cubic and tetragonal phase of SrTiO₃ and BaTiO₃ are studied from ab initio. The calculations are performed in the projector augmented wave densityfunctional theory framework using the local density approximation, gradient corrected...

Physical Review Letters 100(4), 5507 (2008)The strain ﬁeld of isolated screw and edge dislocation cores in aluminum are calculated using densityfunctional theory and a ﬂexible boundary condition method. Nye tensor density contours and differential displacement ﬁelds are used to accurately bound Shockley partial separation distances. Our...

Journal of Alloys and Compounds 459(12), 438446 (2008)Structural and electronic properties of the α and γphases of cerium sesquisulfide, Ce₂S₃, are examined by firstprinciples calculations using the GGA+U extension of density functional theory. The strongly correlated felectrons of Ce are described by a Hubbardtype onsite Coulomb repulsion...

Acc. Chem. Res. 41, 157 (2008)doi: 10.1021/ar700111aAlthough density functional theory is widely used in the computational chemistry community, the most popular density functional, B3LYP, has some serious shortcomings: (i) it is better for maingroup chemistry than for transition metals; (ii) it systematically underestimates reaction barrier heights...

Phys. Rev. B 77, 045136 (2008)We present firstprinciples calculations for the fcc noble gas solids Ne, Ar, and Kr applying the adiabatic connection fluctuationdissipation theorem (ACFDT) to evaluate the correlation energy. The ACFDT allows us to describe longrange correlation effects including London dispersion or van der...

New J. Phys. 10 063020 (2008)A study of the adsorption of CO on late 4d and 5d transition metal (111) surfaces (Ru, Rh, Pd, Ag, Os, Ir and Pt) considering atop and hollow site adsorption is presented. The applied functionals include the gradientcorrected Perdew–Burke–Ernzerhof (PBE) and Becke–Lee–Yang–Parr (BLYP) functionals...

Phys. Rev. B 77, 245202 (2008)Firstprinciples calculations based on hybrid HartreeFock density functionals provide a clear picture of the defect energetics and electronic structure in ZnO. Among the donorlike defects, the oxygen vacancy and hydrogen impurity, which are deep and shallow donors, respectively, are likely to form...

Journal of Applied Physics, 104(3), 034310.doi: 10.1063/1.2968240Molecular dynamics simulations and selected experiments have been carried out to study the growth of Cu films on (010) bcc Ta and the deposition of CuxTa1−x alloy films on (111) fcc Cu. They indicate that fcc Cu films with a (111) texture are always formed when Cu is deposited on Ta surfaces. These...

Solid State Communications 146 324 (2008)Elastic properties of ZnO polymorphs: B4 (wurtzite), B3 (zincblende), B1 (rocksalt) phases, and yet experimentally undiscovered B2 (CsCl) phase were computed using the firstprinciples planewave pseudopotential method in the scheme of density functional theory. The results obtained for the most...
2007

Physical Review B Condensed Matter 75, 195315 (2007)The structure of the Siterminated 3CSiC(001)c(4×2) surface reconstruction is determined using synchrotronradiationbased xray photoelectron diffraction from the Si 2p and C 1s core levels. Only the alternating upanddown dimer (AUDD) model reproduces satisfactorily the experimental results....

Physical Review B Condensed Matter 76, 195440 (2007)We present a detailed study of the adsorption of CO on Cu, Rh, and Pt (111) surfaces in top and hollow sites. The study has been performed using the local density approximation, the gradient corrected functional PBE, and the hybrid HartreeFock density functionals PBE0 and HSE03 within the...

Physical Review B Condensed Matter 75, 195128 (2007)We present density functional theory (DFT) calculations for MnO, Mn₃O₄, αMn₂O₃, and βMnO₂, using different gradient corrected functionals, such as PerdewBurkeErnzerhof (PBE), PBE+U, and the two hybrid density functional HartreeFock methods PBE0 and HeydScuseriaErnzerhof (HSE). We investigate...

Physical Review Letters 99, 217001 (2007)Combining experiments and ab initio models we report on SrPt₄Ge₁₂ and BaPt₄Ge₁₂ as members of a novel class of superconducting skutterudites, where Sr or Ba atoms stabilize a framework entirely formed by Ge atoms. Below Tc=5.35 and 5.10 K forBaPt₄Ge₁₂ and SrPt₄Ge₁₂, respectively, electronphonon...

Physical Review B Condensed Matter 76, 014121 (2007)A systematic investigation of the alkaline earth hydrides BeH₂, MgH₂, CaH₂, SrH₂, BaH₂, the corresponding deuterides, and their antecedent metals is reported. We calculate lattice parameters, electronic and vibrational energies, enthalpies of formation at 0 and 298 K, components of the elasticity...

Physical Review Letters 99, 246403 (2007)Selfconsistent GW calculations, maintaining only the quasiparticle part of the Green's function G, are reported for a wide class of materials, including small gap semiconductors and large gap insulators. We show that the inclusion of the attractive electronhole interaction via an effective...

Applied Catalysis A: General 322, 7691 (2007)This paper is a review of recent advances accomplished in the ﬁeld of hydrotreatment (HDT) sulﬁde catalysts and using theoretical approaches based on the density functional theory (DFT) combined with thermodynamic models and microkinetic models. We illustrate ﬁrst numerous concepts of modern DFT...

Inorganic Chemistry 46(4), 14011409 (2007)doi: 10.1021/ic062032eFirstprinciples modeling, experimental, and thermodynamic methodologies were integrated to facilitate a fundamentally guided investigation of quaternary complex hydride compounds within the bialkali Na−Li−Al−H hydrogen storage system. The integrated approach has broad utility for the discovery,...

Physical Review B Condensed Matter 76, 092102 (2007)By means of a density functional theory approach, we calculated the structural stabilities, electronic structure, elastic constants, and vibrational properties of the compound TiPd₂. The results indicate that the tetragonal MoSi₂type (C11b) structure is unstable, whereas the orthorhombically...

Physical Review B Condensed Matter 76, 014424 (2007)By an ab initio density functional approach, structural, magnetic, vibrational, and thermodynamic properties of HfMn₂ were studied. These properties were derived for the C14, C15, and C36 crystal structures, revealing a close energetical competition between the ferromagnetically ordered phases and...

J. Am. Chem. Soc. 129, 1912 (2007)doi: 10.1021/ja063208eThe layered ternary nitride LiNiN shows an interesting combination of fast Li+ ion diffusion and metallic behavior, properties which suggest potential applications as an electrode material in lithium ion batteries. A detailed investigation of the structure and properties of LiNiN using powder...

Europhysics Letters (EPL) 67(5), 807813 (2007)Based on densityfunctional calculations, we propose that ZrMn₂ is a polymorphic material. We predict that at low temperatures the cubic C15, and the hexagonal C14 and C36 structures of the Laves phase compound ZrMn₂ are nearly equally stable within 0.3 kJ mol⁻¹ or 30 K. This degeneracy occurs when...

Fluid Phase Equilibria (2007) vol. 261 (12) pp. 168175We present molecular simulation results of solubility and selfdiffusion of carbon dioxide and hydrogen sulfide in linear polyethylene melts. Simulations were carried out at 433 K and pressures in the range 0.1–10 MPa. Solubilities were computed using Monte Carlo simulations in the osmotic ensemble...

J. Chem. Phys. 127, 024103 (2007)doi: 10.1063/1.2747249The B3LYP hybrid functional has shown to successfully predict a wide range of molecular properties. For periodic systems, however, the failure to attain the exact homogeneous electron gas limit as well as the semiempirical construction turns out to be a major drawback of the functional. We...

Journal of Alloys and Compounds 446–447, 188–194 (2007)Systematic theoretical results for La(TM)₅Hₙ materials with TM one of the magnetic transition metals Fe, Co, or Ni are discussed. For TM = Co, Ni the antecedent LaCo₅ and LaNi₅ intermetallics and hydrides are well known. While no La–Fe compounds exist, LaFe₅ hydrides are predicted to form by both...
2006

Journal of Chemical Physics 124(15), 4709 (2006)doi: 10.1063/1.2187006Hybrid Fock exchange/density functional theory functionals have shown to be very successful in describing a wide range of molecular properties. For periodic systems, however, the longrange nature of the Fock exchange interaction and the resultant large computational requirements present a major...

Physical Review B Condensed Matter 73, 045112 (2006)In this work we derive closed expressions for the head of the frequencydependent microscopic polarizability matrix in the projectoraugmented wave (PAW) methodology. Contrary to previous applications, the lon gitudinal expression is utilized, resulting in dielectric properties that are largely...

Oil & Gas Science and TechnologyRevue de l'IFP 61(4), 580 (2006)doi:In what follows, it is reported the detailed account of the presentations and discussions taking place at the round table on Molecular Modeling and HighThroughput Experimentation (HTE), meeting the challenges of catalysts, chemicals and materials design. After the short introduction by H. Toulhoat...

GM Research & Development Center, 63 (2006)doi:The present work extends previous work on modeling the effect of a sinusoidal interface pattern on interfacial toughening between identical materials by incorporating both elasticperfectly plastic and elasticpowerlawhardening models. The materials are assumed to be bonded by an infinitesimally...

J. Chem. Phys. 125, 249901 (2006)doi: 10.1063/1.2403866

Journal of Computational Chemistry, 27(15), 1787–1799. (2006)doi: 10.1002/jcc.20495A new density functional (DF) of the generalized gradient approximation (GGA) type for general chemistry applications termed B97D is proposed. It is based on Becke's powerseries ansatz from 1997 and is explicitly parameterized by including damped atompairwise dispersion corrections of the...

J. Mater. Chem.16, 1154 (2006)doi: 10.1039/B514773EWe theoretically examine four hypothetical ternary lanthanide hydrides, CsLn<sup>II</sup>H<sub>3</sub> and Cs<sub>2</sub>Ln<sup>II</sup>H<sub>4</sub>, where Ln<sup>II</sup> = Yb, Tm. We optimize their crystal unit cells in the...
2005

Scripta Materialia 52(3), 205210 (2005)The Rice–Thomson parameter has been evaluated as a computational screening tool for identifying ductilizing additives to Mo. Our results support a hypothesis that soluble additives that are hcp in their pure form weaken the Mo bcc lattice against shears in the (110) plane that are associated with...

Journal of Chemical Physics 122, 234102 (2005)doi: 10.1063/1.1926272Present local and semilocal functionals show significant errors, for instance, in the energetics of small molecules and in the description of band gaps. One possible solution to these problems is the introduction of exact exchange and hybrid functionals. A planewavebased algorithm was implemented...

Applied Physics Letters 87(4), 1910 (2005)doi: 10.1063/1.2000340In order to clarify the allotropic structural properties of TiSi₂ we calculated by means of an ab initio density functional approach the total energies of the C49, C54, and C40 crystal structures of the bulk compound. We found that at T=0 K the C49 structure of TiSi₂ is its most stable phase...

Physical Review B Condensed Matter 72, 125120 (2005)A density functional theory investigation of the recently identiﬁed hydrogen storage reaction LiNH₂ + LiH ↔ Li₂NH + H₂ is described. The electronic structure and enthalpy of formation ΔH of each constituent are calculated in both the generalized gradient approximation (GGA) and the local density...

Journal of Chemical Physics 122, 064707 (2005)doi: 10.1063/1.1849157First principles calculations of the phonon dispersion relations and the phonon density of states for three zeropressure zirconia phases are presented. The phonon dispersion relations of the tetragonal and monoclinic phases do not exhibit the imaginary frequencies, contrary to the cubic phase for...

Materials SciencePoland 23(2), 365 (2005)doi:The simulation of vibrational properties and finite temperature effects based on ab initio calculation of phonons within the direct approach is discussed.

Physical Review B Condensed Matter 72, 054440 (2005)By an ab initio density functional approach the structural and phase stability, electronic and magnetic properties, elastic constants, phonon dispersion, and defect formation of the Lavesphase compound ZrMn₂ for the C15, C14, and C36 crystal structures were investigated. In order to study the...
2004

Physical Review B Condensed Matter 70, 125411 (2004)Optical second harmonic (SH) response of rutile TiO₂(110) surface was studied by the selfconsistent full potential linearized augmented planewave method within the localdensity approximation. The calculated SH response of the relaxed surface agrees with the measured SH intensity as a function of...

Physical Review B Condensed Matter 69, 235401 (2004)Using a ﬁrstprinciples methodology, we investigated the effect of diamond surface termination on the work of separation ( W sep) , interface geometry, bond character, and adhesive transfer of three Al/diamond interfaces, viz., Al(111)/C(111)1×1, Al(111)/C(111)2×1 and Al(111)/C(111)1×1:H. Bond...

Applied Physics Letters 85(16), 3465 (2004)doi: 10.1063/1.1808503We have investigated the energetics of hydrogen site occupation in LaNi₅H_n (hexagonal P63mc structure) and LaCo₅H_n (orthorhombic Cmmm structure) via calculation of the sitedependent enthalpies of hydride formation ΔH. For each structure ΔH was determined for a broad variety of hydrogen...

Applied Physics Letters 85(3), 392 (2004)doi: 10.1063/1.1773924Ab initio calculations of the basic properties of solids have advanced significantly, and it is now possible to simply access a crystal structure database, and from the given constituent atoms and their positions, calculate reasonably accurate values for elastic constants and thermomechanical...

Physical Review B Condensed Matter 69, 195409 (2004)The oxygen coverage, structure, and thermodynamic stability of (0001) surfaces of Fe2O3 (hematite) as a function of temperature and oxygen pressure are investigated by ab initio density functional theory with the generalized gradient approximation. Spinpolarized total energy and force calculations...

Phys. Rev. B 69, 085102 (2004)Band structures and dielectric functions are calculated using densityfunctional theory and localdensity approximation for three βcristobalite modifications of SiO₂ with spacegroup symmetries Fd3m, I4¯2d, and P213. Quasiparticle corrections for the KohnSham eigenvalues are determined in a GW...

Phys. Rev. B 69, 075413 (2004)It is well known that the physical properties of some transitionmetal compounds (mostly oxides) are strongly affected by intraatomic correlations. Very recently, investigations of the adsorption of small molecules such as CO on the surfaces of transitionmetal oxides have led to rather surprising...

Phys. Rev. B 70, 125426 (2004)We present a detailed ab initio investigation of the stability, the structural, electronic, and magnetic properties of the (0001) surfaces of hematite (Fe₂O₃) and chromia or eskolaite (Cr₂O₃). Strong electron correlation effects not included in a densityfunctional description are described by a...

Phys. Rev. B 69, 165107 (2004)Rhombohedral αFe₂O₃ has been studied by using densityfunctional theory (DFT) and the generalized gradient approximation (GGA). For the chosen supercell all possible magnetic configurations have been taken into account. We find an antiferromagnetic ground state at the experimental volume. This...
2003

J. Catalysis 214, 68 (2003)The skeletal isomerization of a 2pentene molecule catalyzed by acidic ZSM22 was investigated by ab initio DFT studies. Two different scenarios proposed in the literature were tested. First a reaction including an alkyl shift was considered: a methyl or ethyl group is detached from the carbenium...

Technical Report OSTI 821509doi: 10.2172/821509Atomistic modeling was used to investigate the effects of impurity elements on the metallurgy, irradiation embrittlement, and environmentally assisted cracking of nickelbase alloys. Calculations were performed via ab initio atomistic modeling on a nickel Σ5 {001} twist grain boundary. A Griffith...

J. Phys.: Condens. Matter 15, 979 (2003)Densityfunctional studies of structural and electronic properties of transitionmetal sulfides formed by 3d transition metals, based on the local spindensity approximation and including nonlocal corrections to the exchange–correlation functional (generalized gradient approximation), have...
2002

Journal of Physical Chemistry B 106(21), 5483 (2002)doi: 10.1021/jp014190rTo predict equilibrium properties of cyclic alkanes using the Gibbs ensemble Monte Carlo method (GEMC), a new transfer move is proposed to sample the configuration space with efficiency. This new method, called reservoir bias Monte Carlo, consists of adapting the reservoir bias insertion in the...

Physical Review B Condensed Matter 66, 224112 (2002)The crystallographic structure of switchable mirror material YD₃ is still under debate. Aiming at a ﬁnal structure assessment, currently considered structure models of P3c1 , P63cm and P63 symmetry are studied by means of ab initio methods. The relative stability of these candidate structures is...

Physical Review B Condensed Matter 65, 104104 (2002)A symmetrygeneral approach for the leastsquares, therefore precise, extraction of elastic coefﬁcients for strained materials is reported. It analyzes stresses calculated ab initio for properly selected strains. The problem, its implementation, and its solution strategy all differ radically from a...

Acta Crystallographica Section B 58(3), 349357 (2002)The timely integration of crystal structure databases, such as CRYSTMET, ICSD etc., with quantum software, like VASP, OresteS, ElectrA etc., allows ab initio cell and structure optimization on existing purephase compounds to be performed seamlessly with just a few mouse clicks. Application to the...

Phys. Rev. B 66, 224409 (2002)It is by now well established that in antiferromagnetic γFe, stabilized in the form of precipitates in a Cu matrix or by epitaxial growth on an appropriate substrate, magnetic and/or crystalline symmetries are broken. Little is known, however, on the physical effects driving the symmetry reduction...

phys. stat. sol. (b) 229, 1155 (2002)Abinitio stiffness values were computed in an automated way for two trigonal reference materials: dextro low quartz and calcite with respective space groups P3₂21 and R3c. Both were computed in their IRE settings, namely with r faces indexed {1011} for rightquartz and with obverse setting of...

Phys. Rev. B 66, 195338 (2002)The linear and nonlinear optical susceptibilities of unreconstructed and reconstructed (2×1) Si(111) clean and hydrogen covered surfaces were studied by application of an ab initio approach, namely the selfconsistent full potential linearized augmented planewave method within the localdensity...
2001

Macromolecular Symposia 171(1), 4556 (2001)The λtransition of elemental sulfur occurring at about 159°C has long been associated with the conversion of cyclic S8 rings (cS8) to amorphous polymer (aS) via a ring opening polymerization. Here we demonstrate, with the use of both density functional and HartreeFock quantum mechanical...

Applied Physics Letters 79(3), 368370 (2001)doi: 10.1063/1.1383282Accurate band structures of binary semiconductors AB (A = Al, Ga, In and B = P, As, Sb) and selected ternary III–V semiconductors were calculated using an allelectron screened exchange approach within the full potential linearized augmented planewave method. Fundamental band gaps and Γ–L and Γ–X...

US Patent 6799089, (2001)doi:For estimating a property of use, for example the activity of a catalyst or the ability to hold a ratioelement in a solid mineral matrix, or a material M.sub.AB whose active element is AB, there are used a descriptor D.sub.AB of the chemical bond between A and B, which has the dimension of an...

Physical Chemistry Chemical Physics 3(1), 8086 (2001)doi: 10.1039/b007281hGrand canonical ensemble Monte Carlo simulations of the adsorption properties of several model faujasite zeolites were performed using the statistical bias method. The results enable a better understanding of the effect of cation exchange in the selective adsorption of binary mixtures of para and...

Physica B: Physics of Condensed Matter 307, 191 (2001)The structure of orthorhombic gallium was ﬁrst determined in 1933 in the space group Cmca. The recent crystal structure literature also consistently uses this setting. The ab initio stiﬀness coeﬃcients calculated from this crystal structure are: C₁₁=88, C₁₂=29, C₁₃=34, C₂₂=116, C₂₃=24, C₃₃=98, C₄₄=...

Physical Review B Condensed Matter 63, 174103 (2001)A symmetrygeneral scheme for the simultaneous leastsquares extraction of the elastic coefﬁcients and of the residual strain components from ab initio total energy calculations on crystal structure models of materials is proposed. It is quite efﬁcient and avoids error propagation. An appropriate,...

J. Phys. Chem. A 105, 895 (2001)doi: 10.1021/jp0031000The energetics of the gasphase SN2 reactions Y⁻ + CH₃X → CH₃Y + X⁻ (X,Y = F,Cl,Br), were studied using (variants on) the recent W1 and W2 ab initio computational thermochemistry methods. These calculations involve CCSD and CCSD(T) coupled cluster methods, basis sets of up to spdfgh quality,...

J. Phys. Chem. A 105, 2936 (2001)doi: 10.1021/jp004262zWe compare hybrid Hartree−Fock densityfunctional theory to ab initio approaches for locating saddle point geometries and calculating barrier heights on a Born−Oppenhiemer potential energy surface. We located reactant, product, and saddle point stationary points for 22 reactions by the MP2 and...

Eur. Phys. J. B 22, 443–453 (2001)We propose a method to simulate aSi and aSi:H using an ab initio approach based on the Harris functional and thermallyamorphisized periodicallycontinued cells with at least 64 atoms. Hydrogen incorporation was achieved via diffusive addition. In preparing samples that may simulate the...
2000

Journal of Physical Chemistry B 104(19), 47454753 (2000)doi: 10.1021/jp994064bAn extension of the anisotropic united atoms model is proposed for thiols and sulfides. A complete derivation of the nonbonded parameters is performed with the aim of obtaining a transferable force field. The electrostatic part of the intermolecular potential is represented by a set of atomic...

Physical Review B Condensed Matter 61(7), 4677 (2000)Quasiparticle electronic band structures for ternary InGaAs and InGaSb systems, modeled by a luzonite structure, have been obtained using the screenedexchange localdensity approximation approach. We focus our attention on energy transitions relevant for the electronhole pair lifetime and, in...

Framework dynamics including computer simulations of the water adsorption isotherm of zeolite NaMAPPhysical Chemistry Chemical Physics 2(18), 42554264 (2000)doi: 10.1039/b003771kComputer simulations of the water adsorption isotherm of zeolite NaMAP have been performed. Both grand canonical molecular dynamics and a combination of Monte Carlo calculations and lattice relaxations (pseudodynamic simulations) have been used to account for the lattice dynamics of the zeolite...

Physical Chemistry Chemical Physics 2(18), 42494254 (2000)doi: 10.1039/b003770mPeriodic density functional calculations on zeolite NaMAP are presented. These calculations used a preliminary model obtained from Xray powder diffraction as starting point and fully optimized the atom positions within the unit cell. It is shown that the structure obtained in the calculation...

Phys. Rev. B 62, 11556–11570 (2000)Spinpolarized calculations in solids have generally been confined to a global quantization axis to simplify both the theoretical model and its implementation in selfconsistent codes. This approximation is justified as many materials exhibit a collinear magnetic order. However, in recent years...

Ab initio methods as an integral part of microelectronic materials modeling: status and perspectivesMaterials Science in Semiconductor Processing 3, 3–11 (2000)The control of materials properties and their relation to the manufacturing processes are central in achieving better performance and lower manufacturing costs of microelectronic devices. To this end, ab initio methods can contribute unique information about materials properties and processes where...
1999

Physical Review B Condensed Matter 59(11), 74137421 (1999)A simple formulation of a generalized gradient approximation for the exchange and correlation energy of electrons has been proposed by Perdew, Burke, and Ernzerhof (PBE) [Phys. Rev. Lett. 77, 3865 (1996)]. Subsequently Zhang and Yang [Phys. Rev. Lett. 80, 890 (1998)] have shown that a slight...

Fluid Phase Equilibria 161(1), 45 (1999)We have employed Monte Carlo simulation in the NPT ensemble to determine the molar volume and the compressibility factor of naturally occurring hydrocarbon gas mixtures. The simulation results were compared to experimental data as well as to predictions based on both the Peng–Robinson and AGA 8...

Physical Review B Condensed Matter 59(3), 1758 (1999)The formal relationship between ultrasoft (US) Vanderbilttype pseudopotentials and Blöchl’s projector augmented wave (PAW) method is derived. It is shown that the total energy functional for US pseudopotentials can be obtained by linearization of two terms in a slightly modiﬁed PAW total energy...

Langmuir 15(25), 86788685 (1999)doi: 10.1021/la990305vThe properties of pxylene and mxylene adsorbed in NaY and KY faujasites have been studied by grand canonical Monte Carlo simulation. Biased particle insertions and deletions were implemented to allow the computation of equilibrium adsorption isotherms of such complex systems. This work is based...

Rev. Modern Phys. 71, S59 (1999)When the 20th century opened, the fields of crystallography, metallurgy, elasticity, magnetism, etc., dealing with diverse aspects of solid matter, were largely autonomous areas of science. Only in the 1940s were these and other fields consolidated into the newly named discipline of "solid...

J. Chem. Phys. 110, 5029 (1999)doi: 10.1063/1.478401In order to discriminate between approximations to the exchangecorrelation energy E<sub>XC</sub>[ρ↑,ρ↓], we employ the criterion of whether the functional is fitted to a certain experimental data set or if it is constructed to satisfy physical constraints. We present extensive test...
1998

Physical Review Letters (1998) vol. 80 (20) pp. 44664469A new iterative Monte Carlo simulation scheme is presented for the efficient prediction of fluid phase equilibria of mixtures containing long chain molecules. Using realistic molecular potentials, the highpressure vaporliquid and liquidliquid equilibria of binary mixtures of ethane or ethylene...

J. Chem. Phys. 108, 6109 (1998)doi: 10.1063/1.476021How the results obtained by computer simulation of molecular systems can be validated is considered. The overall quality of the simulated properties of a molecular system will depend on (i) the quality of the theory or model, (ii) the accuracy of the interatomic interaction function or force field...
1997

Physical Review Letters 78(21), 40634066 (1997)A direct approach to calculate the phonon dispersion using an ab initio force constant method is introduced. The phonon dispersion and structural instability of cubic ZrO₂ are found using a supercell method in the localdensity approximation. The force constants are determined from the Hellmann...

Phys. Rev. Lett. 79, 4353 (1997)We demonstrate that the quantum Monte Carlo (QMC) methodology (i) provides barrier heights and heats of formation within ∼0.05eV of experimental values, (ii) confirms recent measurements for the ring inversion of cyclooctatetraene, and (iii) enables us to predict quantities not yet measured....
1996

Physical Review B Condensed Matter 54(16), 11169 (1996)We present an efﬁcient scheme for calculating the KohnSham ground state of metallic systems using pseudopotentials and a planewave basis set. In the ﬁrst part the application of Pulay’s DIIS method (direct inversion in the iterative subspace) to the iterative diagonalization of large matrices...
1991

Psychological Reports 69, no. 3 (December 1991): 1165–1166TRINKAUS, JOHN, and KAREN DENNIS. “Taste preference for brussels sprouts: an informal look.” Psychological Reports 69, no. 3 (December 1991): 1165–1166.
1989

New York: Oxford University Pressdoi:
1977

J. Am. Chem. Soc 60, 488 (1977)The Young's and shear moduli of polycrystalline monoclinic hafnium oxide were determined by the sonic resonance method at room temperature as a function of volume fraction porosity. The Spriggs equation empirically described the data and the zero porosity moduli as 283.6 GN/m² and 109.2 GN/m²...
1976

J. Appl. Cryst. 10, 73 (1977)A computer program has been written with the aim of calculating powder patterns without the use of crystallographic tables. This has been achieved by deriving all symmetry information such as general equivalent positions from the HermannMauguin spacegroup symbols, by calculating automatically the...
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