MedeA® Phonon: Capturing "Relevant Temperatures"

Before scientists and engineers had today’s computing power, it was often a Herculean effort to capture “relevant temperatures” in modeling scenarios. Our Phonon module takes advantage of technology and our computational materials science expertise to compute temperature-dependent vibrational properties of solids, surfaces, interfaces, molecules and clusters. This provides critical insight into temperature dependent effects.

MedeA Phonon: Capturing "Relevant Temperatures"

Key Benefits of Phonon

  • Ability to describe systems at finite temperatures
  • Predicts material behavior over a wide temperature range
  • Use Phonon to determine phase stability Computes heat capacity, enthalpy, entropy and free energy
  • Describes vibrational modes of molecules on surfaces Handles hundreds of calculations through JobServer/TaskServer

Properties from Phonon module

  • Phonon dispersions
  • Phonon density of states
  • Zero point energy
  • Vibrational part of heat capacity as a function of temperature
  • Vibrational enthalpy, entropy, and free energy as a function of temperature
  • Symmetry analysis of vibrational modes at the center of the Brillouin zone with classification in IR active, Raman active and silent modes

Computational characteristics

  • Automatic detection and use of any space-group symmetry
  • Fully automatic determination of supercell and all necessary atomic displacements
  • Fully automated setup, execution, and processing of VASP jobs
  • Uses forces computed with VASP 5 with any of the functionals available. This includes the ability to use functionals such as GGA+U and hybrid functionals, and fully relativistic Hamiltonians
  • Partial freezing of atoms possible, e.g. to obtain vibrational modes of molecules on surfaces
  • Applicable to transition state geometries to obtain vibrational partition functions for the calculation of reaction and diffusion rates within Eyring’s transition state theory
  • Restart capabilities in case of hardware or communication failures (larger systems may involve several hundred individual tasks, which are controlled automatically by the JobServer)
  • Integrated IR and Raman spectra simulation
  • Improved electronic contributions to free energies
  • Automatic coverage of LO-TO mode split at the zone center
  • Dielectric tensor (vibrational contribution)

Required MedeA® modules