Welcome to the MuST Documentation!#
MuST is a research project supported by the National Science Foundation (NSF) to build a public ab initio electronic structure calculation software package with petascale and beyond computing capability, for first-principles studies of quantum phenomena in disordered materials.
The MuST package is now (as of January 1, 2020) free to download on GitHub (mstsuite) under a BSD 3-clause license.
MuST is developed based on full-potential multiple scattering theory (also known as the Korringa-Kohn-Rostoker method) using the Green’s function approach. It builds upon decades of development of research codes led by Malcolm Stocks and his postdocs and students in the Theory Group of the Metals and Ceramics Division (later Materials Science and Technology Division) at Oak Ridge National Laboratory.
The original research codes include:
Korringa-Kohn-Rostoker Coherent Potential Approximation (KKR-CPA): A highly efficient ab initio method for the study of random alloys.
Locally Self-consistent Multiple Scattering (LSMS) method: A linear-scaling ab initio code capable of treating extremely large disordered systems using the largest parallel supercomputers available.
It was originally suggested by Mark Jarrell, and demonstrated by model calculations, that strong disorder and localization effects can be studied within the LSMS formalism using cluster embedding in an effective medium with the Typical Medium Dynamical Cluster Approximation (TMDCA), enabling a scalable approach for first-principles studies of quantum materials.
The ultimate goal of the MuST project is to provide a computational framework for investigating quantum phase transitions and electron localization in the presence of disorder in real materials, and to enable computational studies of local chemical correlation effects on magnetic structure, phase stability, and mechanical properties of solid-state materials with complex structures.
The starting point of the MuST package is the integration of two research codes:
LSMS (formerly LSMS3) and MST (formerly MST2), both originally based on the
legacy LSMS-1 code developed in the mid-1990s at Oak Ridge National Laboratory.
LSMS#
The LSMS code, maintained by Markus Eisenbach, is primarily written in C++. It
consists of muffin-tin LSMS with an interface for Monte-Carlo simulation drivers.
LSMS is one of the baseline benchmark codes for DOE COREL systems and has been
selected as a CAAR project for exascale computing on the Frontier system. It demonstrates
nearly ideal linear scaling with 96% parallel efficiency on the Titan machine at ORNL.
MST#
The MST code, maintained by Yang Wang, is mainly written in Fortran 90. It focuses
on physics capabilities and serves as a platform for implementing and testing full-potential
multiple scattering theory and its numerical algorithms. It includes LSMS, KKR, and KKR-CPA codes
and supports:
Muffin-tin and full-potential calculations
Non-relativistic, scalar-relativistic, and fully-relativistic approaches
Non-spin-polarized, spin-polarized, and spin-canted ab initio electronic structure calculations
KUBO#
The KUBO code, maintained by Vishnu Raghuraman, is mainly written in Fortran 90. It
implements the Kubo-Greenwood formula within the KKR-CPA framework and calculates the
electrical conductivity of random alloys.