MedeA 2.17 offers a range of enhancements and new capabilities in MedeA environment.
MedeA now possesses a ForcefieldOptimizer capability which uses VASP trajectory information for a system (structures, energies, forces, and stresses) to develop and refine reliable forcefield parameters. The ForcefieldOptimizer employs genetic algorithm and gradient based optimization methods, and provides direct validation and training set support. Currently the ForcefieldOptimizer supports the Buckingham and Embedded Atom Method (EAM) forcefield forms and facilitates the simulation of larger systems and longer timescales than accessible with first-principles methods alone.
The UNiversal CLuster Expansion (UNCLE) interface has been extended and enhanced to support interactive ground state diagram display and analysis, restarts from existing calculations, and the exploration of possible phases based on the incorporation of vacancies. UNCLE allows users to employ the cluster expansion technique for large-scale modeling of composition dependent materials properties including order-disorder phenomena based on VASP first-principles methods.
Extensive enhancements to the MedeA environment have been undertaken including significant enhancements to graphical performance for large structures.
MedeA is the leading environment for atomistic Materials Design, Inc., modeling, and simulation for Windows and Linux environments.
MedeA 2.17 New Features
Support for ionic (Buckingham form) and metallic (EAM form) forcefields
Employs VASP molecular dynamics trajectory information including energy, force, and stresses
Genetic algorithm based search of parameter space
Interactive selection of fitting variables including specification of fitting constraints
Least-squares based optimization of parameters
Extensive reporting of optimization results including estimated parameter errors
Automatically generated analysis of energy and force agreement between optimized forcefield and target training set
Handles training and validation first-principles data sets
Generated forcefields can be imported directly into MedeA® and used with LAMMPS
Improved manipulation and visualization of multiple and fractional site occupation in the structure viewer
Cluster expansion for systems with vacancies is fully supported including customized vacancy concentration ranges
Graphical representation of random mixing results
Updated Monte Carlo user interface and improved handling of temperature schedules
Interactive graphical analysis of Monte Carlo trajectories and temperature profiles
Robust handling of low symmetry and multi-site systems
Customized and fully automatic adaption of the iterative ground state search via Genetic Algorithm for miscible systems or systems with miscibility gap
Graphical representation of binary ground state diagrams from Compressive Sensing simulations
Descriptive help text available from the graphical user interface
Enhancements for flowchart definition and execution
Cation location analysis enhancements
Volumetric property analysis
A range of additional enhancements and updates have been made to the MedeA-GIBBS interface to enhance usability and efficiency.
MedeA-Infrastructure and Builders:
The hybridization state detection of nitrogen species has been enhanced
Powder diffraction pattern range extended
The reporting of progress during amorphous materials construction in Flowcharts has been upgraded
A number of enhancements have been made to standardize MedeA behavior on the Windows and Linux platforms
Significant enhancements to graphical performance for large structures
Mixed mode graphical display capabilities have been extended and enhanced
Flowchart auto-arrange functionality has been added
Subset management enhancement