Introduction
THE GWL CODE Why this code This code has been conceived with the purpose of enabling GW-BSE calculations in large model structures, as for such systems sums over empty states become a serious issue we devised a method to eliminate them completely from the calculation. Note that the main GW-BSE codes support Gamma-only sampling and work with norm-conserving pseudopotentials. The package contains also the SIMPLE codes which support k-points sampling albeit preservig sums over empty orbitals. Main features GW G0W0 approximation Basis for polarizability operators: G vectors or optimal basis sets No sums over empty states Treatment of isolated and extended systems Analytic continuation approach collinear spin polarization NEW: full-linear response formulation without storing W NEW: fast and approximate e-ph coupling Main features BSE Tamm-Dancoff approximation No sums over empty orbitals W can be calculated on-the-fly through linear response Treatment of isolated and extended systems Calculation of complex dielectric function through Lanczos algorithm Calculation of excited states Real-Space Real-Time TD-BSE collinear spin polarization NEW: fast and approximate e-ph coupling Main features SIMPLE RPA and BSE calculation of optical spectra collinear spin or full-relativistic SOC Use of reduced Shirley's bases for KS orbitals and for their products Main features not released yet or under development Contour integration off-diagonal self-energy terms approximate treatment of semicore states partially occupied states DISCLAIMER: These programs are distributed in the hope that they will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Introduction

THE GWL CODE

Why this code

This code has been conceived with the purpose of enabling GW-BSE calculations in large model structures, as for such systems sums over empty states become a serious issue we devised a method to eliminate them completely from the calculation. Note that the main GW-BSE codes support Gamma-only sampling and work with norm-conserving pseudopotentials.
The package contains also the SIMPLE codes which support k-points sampling albeit preservig sums over empty orbitals.

Main features GW

G0W0 approximation
Basis for polarizability operators: G vectors or optimal basis sets
No sums over empty states
Treatment of isolated and extended systems
Analytic continuation approach
collinear spin polarization
NEW: full-linear response formulation without storing W
NEW: fast and approximate e-ph coupling

Main features BSE

Tamm-Dancoff approximation
No sums over empty orbitals
W can be calculated on-the-fly through linear response
Treatment of isolated and extended systems
Calculation of complex dielectric function through Lanczos algorithm
Calculation of excited states
Real-Space Real-Time TD-BSE
collinear spin polarization
NEW: fast and approximate e-ph coupling

Main features SIMPLE

RPA and BSE calculation of optical spectra
collinear spin or full-relativistic SOC
Use of reduced Shirley's bases for KS orbitals and for their products

Main features not released yet or under development

Contour integration
off-diagonal self-energy terms
approximate treatment of semicore states
partially occupied states

DISCLAIMER:
These programs are distributed in the hope that they will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.