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Stand-alone packages

In the following we provide links to three center-related highly recommended stand-alone software packages to treat weakly and strongly correlated materials. They have been developed by several of our Comscope software developers at different institutions and partly serve as basis for Comsuite. The software packages are maintained and supported by their developers.

FlapwMBPT (Full-potential Linearized Augmented Plane Wave method and Many Body Perturbation Theory) is a computer code implementing many body diagrammatic approaches to study electronic structure and ground state properties of materials in their (periodic) crystalline state.

Electronic structure computations are a basic building block for the theoretical calculation of material properties. It can be understood as an eigenvalue problem in which the determination of the electron self-energy matrix Σ is the main challenge. FlapwMBPT offers several first-principle and many body diagrammatic approaches with different levels of approximations to Σ. Currently available approximations include the Local Density Approximation (LDA) which we use to generate an initial approximation for the Green function in many body approaches, but it can be used on its own as well. Also available are a self-consistent Hartree-Fock approximation and a self-consistent GW approximation (scGW). The latter can be combined with a linearized quasi-particle approximation to form our version of the self-consistent quasiparticle GW method (LQSGW). Both scGW and LQSGW are implemented in a fully relativistic way (based on Dirac equations).

An essential new feature of the code consists in the recently implemented self-consistent diagrammatic approaches which go beyond the GW approximation. This feature (so-called scGWΓ, with Γ being the vertex function) can be considered as a new ab initio, diagrammatic tool to study materials with weak to modest strength of correlations. Learn more

EDRIXS is a toolkit for the simulations of resonant inelastic x-ray scattering (RIXS) and x-ray absorption (XAS) spectra of strongly correlated materials based on exact diagonalization (ED) of certain model Hamiltonians. At Comscope, it is used to interpret RIXS spectra of d-electron materials obtained at the Soft Inelastic X-ray (SIX) beamline at NSLS-II. EDRIXS will be integrated into Comsuite as a post-processing module based on DFT+DMFT calculations. Learn more

CyGutz: (DFT +) G-RISB

main developer: Yongxin Yao
supported by: Nicola Lanata, Gabriel Kotliar, Cai-Zhuang Wang, Kai-Ming Ho 
hosted by: Ames Laboratory
DownloadInstallation Guide

CyGutz solves a generic multi-band Hubbard model (including local correlated orbitals and nonlocal orbitals) using the Gutzwiller rotationally invariant slave-boson method (G-RISB). CyGutz can handle (tight-binding) models and has an interface to WIEN2k to treat realistic materials with different degrees of electron correlations. CyGutz yields ground properties with comparable accuracy to DFT+DMFT(+CTQMC), but it is over two-orders of magnitude faster. It can handle all the possible local symmetries without introducing further approximations. CyGutz consists of programs, executables, and scripts written in Fortran90, C (C++), and Python 2.7. The stable version of the CyGutz package is open source under a BSD license and is available for download while the version in active development is available upon request. Learn more

EDMFTF:  DFT + Embedded DMFT Functional

main developer: Kristjan Haule
supported by: Gheorghe L. Pascut
hosted by: Rutgers University

EDMFTF is a highly efficient software package implementing the combination of Density Functional Theory (DFT) with the Embedded Dynamical Mean Field Theory (EDMFT) [JPSJ 87, 041005 (2018)], which is derived from the stationary Luttinger-Ward functional [Phys. Rev. Lett. 115, 256402 (2015)]. DFT is based upon the WIEN2k package. Learn more