Here is a list of codes developed and/or used in the EUSpecLab project

Density Functional Theory codes

Abinit is a general purpose DFT code with many functionalities, in particular ground state calculations as well as dielectric properties and vibrational modes using density functional perturbation theory. 

FHI-AIMS is a general purpose all electron DFT code based on local basis set formalism allowing for calculations of ground states, vibrational modes through density functional perturbation theory and ab-initio molecular dynamics.

RSPt is a full-potential linear muffin-tin orbital (LMTO) code which allows to study ground state properties but also provides interatomic exchange parameters. Calculations beyond DFT are possible using DFT+U or the dynamical mean field theory extension of the code.

GPAW is an open source, general purpose electronic structure code based on the Projector Augmented Wave (PAW)method. GPAW is written in Python and its modular structure makes its source code fairly accessible to code developers. As a unique feature, GPAW can perform DFT calculations using one of three different basis sets: plane waves, uniform real space grids, and numerical atomic orbitals. This is very useful as different problems often call for different basis sets. In addition to the standard DFT functionality, GPAW supports numerous more advanced features. For a full description see https://wiki.fysik.dtu.dk/gpaw/documentation/basic.html

ADF and BAND are molecular and periodic DFT codes in the Amsterdam Modeling Suite (AMS), respectively. Both DFT codes are using all-electron, Slater-type basis sets, which in combination with the scalar and spin-orbit relativistic Hamiltonians enable the accurate description of spectroscopic core electron properties such as EPR, NMR, and X-ray absorption.

Munich SPR-KKR band structure program package: The SPRKKR-package allows to calculate the electronic structure of arbitrary three-dimensional periodic systems, including in particular systems with chemical disorder. The treatment of two dimensional periodic systems (e.g. surfaces) can be done by using an auxiliary system having three dimensional periodicity or by making use of the cluster approximation (for a more appropriate approach see: SPR-TB-KKR band structure program package). Electronic structure calculations can be done in a non-relativistic, scalar-relativistic as well as fully relativistic mode. In the scalar-relativistic mode paramagnetic as well as spinpolarised systems can be treated, including non-collinear spin structures and arbitrary spin spirals. In the fully relativistic mode, paramagnetic as well as spin-polarised systems with an arbitrary spin configuration can be dealt with. On the basis of the electronic structure calculation many different properties can be investigated by means of the SPRKKR-package, with a strong emphasise on response functions and spectroscopic properties including dichroic effects. These type of calculations are in general restricted to the fully relativistic mode. The program is available to interested users under conditions described in the licence agreement form that should be signed and sent via fax or regular mail to H. Ebert. A brief description of the planned application has been added to see whether the Munich SPR-KKR package is suitable or not.

Excited state codes

Abinit also carries out calculations within the GW and BSE approximations for charged and neutral excitations.

Spr-KKR incorporates TD-DFT based XAS calculations and also LDA+DMFT

FHI-AIMS can also calculate energies of excited and charged states through 𝚫Kohn-Sham, GW and RT-TDDFT schemes.

RSPt allows to calculate spectroscopy data from DFT+DMFT and is especially well suited for correlated systems. Available spectroscopies are XAS/XMCD spectra as well as XPS.

Molecular DFT code ADF has fast TDDFT methods such as TD-DFT+TB, sTDDFT, PolTDDFT, and Slater Transition potential, as well as beyond (TD)DFT methods such as qsGW+BSE. Most methods can include continuum and polarizable discrete embedding as well as fully self-consistent spin-orbit coupling (phosphorescence). XES and NEXAFS are accessible through excitations from or to specific orbitals or specific energy windows. Higher-order non-linear optical properties such as two-photon absorption are available as well.
Periodic excited state calculations for surfaces and bulk can be performed with time-dependent current density functional theory (TDCDFT) in BAND. Periodic qsGW+BSE is under development.
Very fast molecular excitations for UV/VIS are available through TDDFTB.

Other spectroscopies

MsSpec is a multiple scattering code calculating the cross-section of different spectroscopies such as photoelectron diffraction, Auger diffraction, LEED, XAS or Auger-photoelectron coincidence spectroscopy using various algorithms allow it to cover kinetic energies up to 2000 eV. It can take the potential and wave functions coming from a DFT calculation as an input. For this, it is at present interfaced with LMTO, SPR-KKR. It can also be used as an ASE calculator.

In the Amsterdam Modeling Suite (AMS), IR, phonons, and related properties are available through the central AMS driver for any engine that gives it forces. This includes the DFT codes ADF and BAND, as well as fast approximate methods such as DFTB and machine learned force fields. Besides the previously mentioned spectroscopy ADF has capabilities for CD, MCD, XMCD, VCD, Mössbauer, NRVS, XPS.

SPR- KKR is a multiple scattering code calculating:

  • Different spectroscopies:
    • X-ray absorption spectroscopy.
    • X-ray emission spectroscopy.
    • X-ray magneto-optics.
    • Non-relativistic Appearance Potential Spectroscopy.
    • Non-relativistic Appearance Potential Spectroscopy.
    • X-ray Photoemission spectroscopy.
    • Magnetic Compton profile.
    • Positron annihilation.
  • Optics for disordered systems:
    • Angle resolved photoemission calculations
    • Photoelectron diffraction
    • Spin polarized LEED calculations

Workflow and scripting engines

The Atomic Simulation Environment (ASE) is a versatile Python library/scripting environment that supports and simplifies many of tasks encountered when working with atomic structures and running DFT calculations. ASE implements interfaces to a number of different atomic simulation codes, though some interfaces are more developed than others. For more information see https://wiki.fysik.dtu.dk/ase/

TaskBlaster is a general Python framework for constructing and executing computational workflows. TaskBlaster implements a Workflow class that can be used to setup complex and dynamic simulation workflows composed of smaller ‘Tasks’ (essentially Python functions). The Atomic Simulation Recipes (ASR) is a library of generic Tasks and Workflows for common types of simulations (see documentation). While TaskBlaster is completely generic, many of the Tasks/Workflows in the ASR library are currently dependent on the GPAW electronic structure code. It should be noted that the ASR library is under development.

Abipy is a python framework to prepare inputs and run jobs with abinit. In particular, phonon and electron band structures can be calculated within an extensive set of established and tested workflows.

PMSCO (PEARL multiple scattering cluster optimization for photoelectron diffraction experiments). PMSCO is a framework of computer programs to calculate photoelectron diffraction patterns and to optimize structural models with reference to measured data. The code uses machine learning techniques to efficiently converge on a best-fit structure in a multi-dimensional parameter space.

ASE2SPRKKR package provide an interface that allow use of the SPRKKR package to electronic structure calculation within Atomic Simulation Environment (abbreviated as ASE) — Python tool that integrates the various tools for electronic structure calculation.

XBAND is a graphical user interface (GUI) that supplies a number of basic functionalities to facilitate the use of a band structure program. It has been developed primarily to support the use of the SPRKKR package of H. Ebert et al., it can easily be modified to support other packages as well.

The python library for automatic simulations (PLAMS) enables easy python scripting of your own workflows around the engines and analysis tools in AMS, which also includes parametrization tools (ParAMS), and an interface to ASE.

Machine learning software

SPR-KKR ARPES calculation machine learning software under development.

ParAMS in AMS2024 enables active learning machine learning potentials, which can be trained to reproduce spectroscopic properties such as IR, Raman, and phonons.