DebiChem Ab initio calculations packages

ABINIT is a package whose main program allows one to find the total energy, charge density and electronic structure of systems made of electrons and nuclei (molecules and periodic solids) within Density Functional Theory (DFT), using pseudopotentials and a planewave basis.

ABINIT also includes options to optimize the geometry according to the DFT forces and stresses, or to perform molecular dynamics simulations using these forces, or to generate dynamical matrices, Born effective charges, and dielectric tensors. Excited states can be computed within the Time-Dependent Density Functional Theory (for molecules), or within Many-Body Perturbation Theory (the GW approximation). In addition to the main ABINIT code, different utility programs are provided.

This package contains the executables needed to perform calculations (however, pseudopotentials are not supplied). For a set of pseudopotentials, install the abinit-data package.

ACESIII is an electronic structure calculation program with a focus on correlated methods. It is the parallel successor to ACESII, employing the Super Instruction Assembly Language (SIAL) as parallelization framework. Features include:

Energies, analytic gradients and analytic hessians for the following methods:

• Restricted/unrestricted spin or restricted open-shell Hartree-Fock (HF)
• Second-order Moeller-Plesset pertubation theory (MP2)

Energies and analytic gradients for the following methods:

• Coupled cluster singles and doubles (CCSD)

Additionally, it can compute energies for the following methods:

• Coupled cluster singles and doubles with pertubative triples (CCSD(T))
• Quadratic configuration-interaction singles and doubles (QCISD)

Excited states can be calculated by the following methods:

• Qadratic configuration interaction singles and doubles
• Coupled cluster equation-of-motion (EOM-CC)

It also includes an internal coordinate geometry optimizer. If analytic gradients are not available, numerical gradients via finite differences are used.

CP2K is a program to perform simulations of solid state, liquid, molecular and biological systems. It is especially aimed at massively parallel and linear scaling electronic structure methods and state-of-the-art ab-initio molecular dynamics (AIMD) simulations.

CP2K is optimized for the mixed Gaussian and Plane-Waves (GPW) method based on pseudopotentials, but is able to run all-electron or pure plane-wave/Gaussian calculations as well. Features include:

Ab-initio Electronic Structure Theory Methods using the QUICKSTEP module:

• Density-Functional Theory (DFT) energies and forces
• Hartree-Fock (HF) energies and forces
• Moeller-Plesset 2nd order perturbation theory (MP2) energies and forces
• Random Phase Approximation (RPA) energies
• Gas phase or Periodic boundary conditions (PBC)
• Basis sets include various standard Gaussian-Type Orbitals (GTOs), Pseudo- potential plane-waves (PW), and a mixed Gaussian and (augmented) plane wave approach (GPW/GAPW)
• Norm-conserving, seperable Goedecker-Teter-Hutter (GTH) and non-linear core corrected (NLCC) pseudopotentials, or all-electron calculations
• Local Density Approximation (LDA) XC functionals including SVWN3, SVWN5, PW92 and PADE
• Gradient-corrected (GGA) XC functionals including BLYP, BP86, PW91, PBE and HCTH120 as well as the meta-GGA XC functional TPSS
• Hybrid XC functionals with exact Hartree-Fock Exchange (HFX) including B3LYP, PBE0 and MCY3
• Double-hybrid XC functionals including B2PLYP and B2GPPLYP
• Additional XC functionals via LibXC
• Dispersion corrections via DFT-D2 and DFT-D3 pair-potential models
• Non-local van der Waals corrections for XC functionals including B88-vdW, PBE-vdW and B97X-D
• DFT+U (Hubbard) correction
• Density-Fitting for DFT via Bloechl or Density Derived Atomic Point Charges (DDAPC) charges, for HFX via Auxiliary Density Matrix Methods (ADMM) and for MP2/RPA via Resolution-of-identity (RI)
• Sparse matrix and prescreening techniques for linear-scaling Kohn-Sham (KS) matrix computation
• Orbital Transformation (OT) or Direct Inversion of the iterative subspace (DIIS) self-consistent field (SCF) minimizer
• Local Resolution-of-Identity Projector Augmented Wave method (LRIGPW)
• Absolutely Localized Molecular Orbitals SCF (ALMO-SCF) energies for linear scaling of molecular systems
• Excited states via time-dependent density-functional perturbation theory (TDDFPT)

Ab-initio Molecular Dynamics:

• Born-Oppenheimer Molecular Dynamics (BOMD)
• Ehrenfest Molecular Dynamics (EMD)
• PS extrapolation of initial wavefunction
• Time-reversible Always Stable Predictor-Corrector (ASPC) integrator
• Approximate Car-Parrinello like Langevin Born-Oppenheimer Molecular Dynamics (Second-Generation Car-Parrinello Molecular Dynamics)

Mixed quantum-classical (QM/MM) simulations:

• Real-space multigrid approach for the evaluation of the Coulomb interactions between the QM and the MM part
• Linear-scaling electrostatic coupling treating of periodic boundary conditions
• Adaptive QM/MM

Further Features include:

• Single-point energies, geometry optimizations and frequency calculations
• Several nudged-elastic band (NEB) algorithms (B-NEB, IT-NEB, CI-NEB, D-NEB) for minimum energy path (MEP) calculations
• Global optimization of geometries
• Solvation via the Self-Consistent Continuum Solvation (SCCS) model
• Semi-Empirical calculations including the AM1, RM1, PM3, MNDO, MNDO-d, PNNL and PM6 parametrizations, density-functional tight-binding (DFTB) and self-consistent-polarization tight-binding (SCP-TB), with or without periodic boundary conditions
• Classical Molecular Dynamics (MD) simulations in microcanonical ensemble (NVE) or canonical ensmble (NVT) with Nose-Hover and canonical sampling through velocity rescaling (CSVR) thermostats
• Metadynamics including well-tempered Metadynamics for Free Energy calculations
• Classical Force-Field (MM) simulations
• Monte-Carlo (MC) KS-DFT simulations
• Static (e.g. spectra) and dynamical (e.g. diffusion) properties
• ATOM code for pseudopotential generation
• Integrated molecular basis set optimization

CP2K does not implement conventional Car-Parrinello Molecular Dynamics (CPMD).

Elk is an all-electron full-potential linearised augmented-plane wave (FP-LAPW) code. By not including pseudo-potentials, Elk can provide very reliable high-precision results and works for every chemical element. Features include:

• FP-LAPW basis with local-orbitals
• APW radial derivative matching to arbitrary orders at muffin-tin surface (super-LAPW, etc.)
• Arbitrary number of local-orbitals allowed (all core states can be made valence for example)
• Total energies resolved into components
• LSDA and GGA functionals available
• Isolated molecules or periodic systems
• Core states treated with the radial Dirac equation

Elk is parallelized via OpenMP.

ErgoSCF is a quantum chemistry program for large-scale self-consistent field calculations. It employs modern linear scaling techniques like fast multipole methods, hierarchic sparse matrix algebra, density matrix purification, and efficient integral screening. Linear scaling is achieved not only in terms of CPU usage but also memory utilization. It uses Gaussian basis sets.

It can compute single-point energies for the following methods:

• Restricted and unrestricted Hartree-Fock (HF) theory
• Restricted and unrestricted Kohn-Sham density functional theory (DFT)
• Full Configuration-Interaction (FCI)

The following Exchange-Correlational (XC) density functionals are included:

• Local Density Approximation (LDA)
• Gradient-corrected (GGA) XC functionals BLYP, BP86, PW91 and PBE
• Hybrid XC functionals B3LYP, BHandHLYP, PBE0 and CAMB3LYP

Further features include:

• Linear response calculations (polarizabilities and excitation energies) for restricted reference densities
• External electric fields
• Electron dynamics via Time-Dependent Hartree-Fock (TDHF)

MPQC is an ab-inito quantum chemistry program. It is especially designed to compute molecules in a highly parallelized fashion.

It can compute energies and gradients for the following methods:

• Closed shell and general restricted open shell Hartree-Fock (HF)
• Density Functional Theory (DFT)
• Closed shell second-order Moeller-Plesset pertubation theory (MP2)

Additionally, it can compute energies for the following methods:

• Open shell MP2 and closed shell explicitly correlated MP2 theory (MP2-R12)
• Second order open shell pertubation theory (OPT2[2])
• Z-averaged pertubation theory (ZAPT2)

It also includes an internal coordinate geometry optimizer.

MPQC is built upon the Scientific Computing Toolkit (SC).

NWChem is a computational chemistry program package. It provides methods which are scalable both in their ability to treat large scientific computational chemistry problems efficiently, and in their use of available parallel computing resources from high-performance parallel supercomputers to conventional workstation clusters.

NWChem can handle:

• Molecular electronic structure methods using gaussian basis functions for high-accuracy calculations of molecules
• Pseudopotentials plane-wave electronic structure methods for calculating molecules, liquids, crystals, surfaces, semi-conductors or metals
• Ab-initio and classical molecular dynamics simulations
• Mixed quantum-classical simulations
• Parallel scaling to thousands of processors

Features include:

• Molecular electronic structure methods, analytic second derivatives:
• Restricted/unrestricted Hartree-Fock (RHF, UHF)
• Restricted Density Functional Theory (DFT) using many local, non-local (gradient-corrected) or hybrid (local, non-local, and HF) exchange-correlation potentials
• Molecular electronic structure methods, analytic gradients:
• Restricted open-shell Hartree-Fock (ROHF)
• Unrestricted Density Functional Theory (DFT)
• Second-order Moeller-Plesset perturbation theory (MP2), using RHF and UHF reference
• Complete active space SCF (CASSCF)
• Time-Dependent Density Functional Theory (TDDFT)
• Molecular electronic structure methods, single-point energies:
• MP2 with resolution of the identity integral approximation (RI-MP2) or spin-component scaled approach (SCS-MP2), using RHF and UHF reference
• Coupled cluster singles and doubles, triples or pertubative triples (CCSD, CCSDT, CCSD(T)), with RHF and UHF reference
• Configuration interaction (CISD, CISDT, and CISDTQ)
• Second-order approximate coupled-cluster singles doubles (CC2)
• State-specific multireference coupled cluster methods (MRCC) (Brillouin-Wigner (BW-MRCC) and Mukherjee (Mk-MRCC) approaches)
• Further molecular electronic structure features:
• Geometry optimization including transition state searches, constraints and minimum energy paths (via the Nudged Elastic Band (NEB) and Zero Temperature String methods)
• Vibrational frequencies
• Equation-of-motion (EOM)-CCSD, EOM-CCSDT, EOM-CCSD(T), CC2, Configuration-Interaction singles (CIS), time-dependent HF (TDHF) and TDDFT, for excited states with RHF, UHF, RDFT, or UDFT reference
• Solvatisation using the Conductor-like screening model (COSMO) for RHF, ROHF and DFT, including analytical gradients
• Hybrid calculations using the two- and three-layer ONIOM method
• Relativistic effects via spin-free and spin-orbit one-electron Douglas-Kroll and zeroth-order regular approximations (ZORA) and one-electron spin-orbit effects for DFT via spin-orbit potentials
• Pseudopotential plane-wave electronic structure:
• Pseudopotential Plane-Wave (PSPW), Projector Augmented Wave (PAW) or band structure methods for calculating molecules, liquids, crystals, surfaces, semi-conductors or metals
• Geometry/unit cell optimization including transition state searches
• Vibrational frequencies
• LDA, PBE96, and PBE0 exchange-correlation potentials (restricted and unrestricted)
• SIC, pert-OEP, Hartree-Fock, and hybrid functionals (restricted and unrestricted)
• Hamann, Troullier-Martins and Hartwigsen-Goedecker-Hutter norm-conserving pseudopotentials with semicore corrections
• Wavefunction, density, electrostatic and Wannier plotting
• Band structure and density of states generation
• Car-Parrinello ab-initio molecular dynamics (CPMD):
• Constant energy and constant temperature dynamics
• Verlet algorithm for integration
• Geometry constraints in cartesian coordinates
• Classical molecular dynamics (MD):
• Single configuration energy evaluation
• Energy minimization
• Molecular dynamics simulation
• Free energy simulation (multistep thermodynamic perturbation (MSTP) or multiconfiguration thermodynamic integration (MCTI) methods with options of single and/or dual topologies, double wide sampling, and separation- shifted scaling)
• Force fields providing effective pair potentials, first order polarization, self consistent polarization, smooth particle mesh Ewald (SPME), periodic boundary conditions and SHAKE constraints
• Mixed quantum-classical:
• Mixed quantum-mechanics and molecular-mechanics (QM/MM) minimizations and molecular dynamics simulations
• Quantum molecular dynamics simulation by using any of the quantum mechanical methods capable of returning gradients.

OpenMX (Open source package for Material eXplorer) is a program package for nano-scale material simulations based on density functional theories (DFT), norm-conserving pseudopotentials and pseudo-atomic localized basis functions. Since the code is designed for the realization of large-scale ab initio calculations on parallel computers, it is anticipated that OpenMX can be a useful and powerful tool for nano-scale material sciences in a wide variety of systems such as biomaterials, carbon nanotubes, magnetic materials, and nanoscale conductors.

PSI3 is an ab-initio quantum chemistry program. It is especially designed to accurately compute properties of small to medium molecules using highly correlated techniques.

It can compute energies and gradients for the following methods:

• Closed shell and general restricted open shell Hartree-Fock (RHF/ROHF) (including analytical hessians for RHF)
• Closed shell Moeller-Plesset pertubation theory (MP2)
• Complete active space SCF (CASSCF)
• Coupled-cluster singles doubles (CCSD)
• Coupled-cluster singles doubles with pertubative triples (CCSD(T)) (only for unrestricted (UHF) reference wavefunctions)

Additionally, it can compute energies for the following methods:

• Unrestricted open shell Hartree-Fock (UHF)
• Closed/open shell Moeller-Plesset pertubation theory (MP2)
• Closed shell explicitly correlated MP2 theory (MP2-R12) and spin-component scaled MP2 theory (SCS-MP2)
• Multireference configuration-interaction (MRCI)
• Coupled-cluster singles doubles with pertubative triples (CCSD(T))
• Second/third-order approximate coupled-cluster singles doubles (CC2/CC3)
• Multireference coupled-cluster singles doubles (MRCCSD)
• Closed shell and general restricted open shell equation-of-motion coupled- cluster singles doubles (EOM-CCSD)

Further features include:

• Flexible, modular and customizable input format
• Excited state calculations with the CC2/CC3, EOM-CCSD, CASSCF, MRCI and MRCCSD methods
• Internal coordinate geometry optimizer
• Harmonic frequencies calculations
• One-electron properties like dipole/quadrupole moments, natural orbitals, electrostatic potential, hyperfine coupling constants or spin density
• Utilization of molecular point-group symmetry to increase efficiency

PSI4 is an ab-initio quantum chemistry program. It is especially designed to accurately compute properties of small to medium molecules using highly correlated techniques. PSI4 is the parallelized successor of PSI3 and includes many state-of-the-art theoretical methods.

It can compute energies and gradients for the following methods:

• Restricted, unrestricted and general restricted open shell Hartree-Fock (RHF/ROHF)
• Restricted, unrestricted and general restricted open shell Densitry-Functional Theory, including density-fitting (DF-DFT)
• Density Cumulant Functional Theory (DCFT)
• Closed-shell Density-fitted Moeller-Plesset perturbation theory (DF-MP2)
• Unrestricted Moeller-Plesset perturbation theory (MP2)
• Orbital-Optimized MP2 theory (OMP2)
• Third order Moeller-Plesset perturbation theory (MP3)
• Orbital-Optimized MP3 theory (OMP3)
• Coupled-cluster singles doubles (CCSD)
• Coupled-cluster singles doubles with perturbative triples (CCSD(T)) (only for unrestricted (UHF) reference wavefunctions)
• Equation-of-motion coupled-cluster singles doubles (EOM-CCSD)

Additionally, it can compute energies for the following methods:

• Closed/open shell Moeller-Plesset perturbation theory (MP2)
• Spin-component scaled MP2 theory (SCS-MP2)
• Fourth order Moeller-Plesset perturbation theory (MP4)
• Density-fitted symmetry-adapted perturbation theory (DF-SAPT)
• Multireference configuration-interaction (MRCI)
• Closed-shell Density-fitted coupled-cluster singles doubles (DF-CCSD)
• Closed-shell Density-fitted Coupled-cluster singles doubles with perturbative triples (DF-CCSD(T))
• Second/third-order approximate coupled-cluster singles doubles (CC2/CC3)
• Mukherjee Multireference coupled-cluster singles doubles theory (mk-MRCCSD)
• Mukherjee Multireference coupled-cluster singles doubles with perturbative triples theory (mk-MRCCSD(T))
• Second order algebraic-diagrammatic construction theory (ADC(2))
• Quadratic configuration interaction singles doubles (QCISD)
• Quadratic configuration interaction singles doubles with perturbative triples (QCISD(T))

Further features include:

• Flexible, modular and customizable input format via python
• Excited state calculations with the EOM-CC2/CC3, EOM-CCSD, ADC(2), MRCI and mk-MRCC methods
• Utilization of molecular point-group symmetry to increase efficiency
• Internal coordinate geometry optimizer
• Harmonic frequencies calculations (via finite differences)
• Potential surface scans
• Counterpoise correction
• One-electron properties like dipole/quadrupole moments, transition dipole moments, natural orbitals occupations or electrostatic potential
• Composite methods like complete basis set extrapolation or G2/G3

Quantum ESPRESSO (formerly known as PWscf) is an integrated suite of computer codes for electronic-structure calculations and materials modeling at the nanoscale. It is based on density-functional theory, plane waves, and pseudopotentials (both norm-conserving, ultrasoft, and PAW).

Features include:

• Ground-state single-point and band structure calculations using plane-wave self-consistent total energies, forces and stresses
• Separable norm-conserving and ultrasoft (Vanderbilt) pseudo-potentials, PAW (Projector Augmented Waves)
• Various exchange-correlation functionals, from LDA to generalized-gradient corrections (PW91, PBE, B88-P86, BLYP) to meta-GGA, exact exchange (HF) and hybrid functionals (PBE0, B3LYP, HSE)
• Car-Parrinello and Born-Oppenheimer Molecular Dynamics
• Structural Optimization including transition states and minimum energy paths
• Spin-orbit coupling and noncollinear magnetism
• Response properties including phonon frequencies and eigenvectors, effective charges and dielectric tensors, Infrared and Raman cross-sections, EPR and NMR chemical shifts
• Spectroscopic properties like K- and L1-edge X-ray Absorption Spectra (XAS) and electronic excitations