Program structure#
import veloxchem as vlx
The VeloxChem program adopts a layered Python/C++ language structure.
You can use the standard functions to get a more detailed view of the Python layer. The help function will give you a package description, stating the copyright agreement.
help(vlx)
Help on package veloxchem:
NAME
veloxchem
DESCRIPTION
# VELOXCHEM
# ----------------------------------------------------
# An Electronic Structure Code
#
# SPDX-License-Identifier: BSD-3-Clause
#
# Copyright 2018-2025 VeloxChem developers
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this
# list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
# 3. Neither the name of the copyright holder nor the names of its contributors
# may be used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
PACKAGE CONTENTS
__main__
aodensitymatrix
aoindices
atombdedriver
atomtypeidentifier
batchsize
blockdavidson
c2diis
c6driver
checkpoint
cli
conformergenerator
cpcmdriver
cphfsolver
cppsolver
cubicgrid
cubicresponsedriver
densityviewer
densityvieweralternative
dftutils
dispersionmodel
distributedarray
doubleresbeta
embedding
environment
errorhandler
evbdataprocessing
evbdriver
evbfepdriver
evbreporter
evbsystembuilder
excitedstateanalysisdriver
excitondriver
features
firstorderprop
fockdriver
gradientdriver
griddriver
hessiandriver
hessianorbitalresponse
imdatabasedriver
imdatabasepointcollecter
imforcefieldgenerator
impescoordinates
impesdriver
inputparser
interpolationdatapoint
interpolationdriver
linearsolver
lreigensolver
lreigensolverunrest
lrsolver
lrsolverunrest
main
matrices
matrix
mklconf
mmdriver
mmforcefieldgenerator
mmgradientdriver
mofbuilder
mofmdprepare
mofoptimizer
mofpreparer
mofutils
mointsdriver
molecularbasis
molecularorbitals
molecule
mp2driver
mpitask
nonlinearsolver
numerovdriver
oneeints
openmmdriver
openmmdynamics
openmmgradientdriver
optimizationdriver
optimizationengine
orbitalviewer
outputstream
peforcefieldgenerator
polarizabilitygradient
polorbitalresponse
profiler
pubchemfetcher
pulsedrsp
quadraticresponsedriver
reactionmatcher
reaffbuilder
respchargesdriver
rifockdriver
rigradientdriver
rspabsorption
rspc6
rspcdspec
rspcustomproperty
rspdoublerestrans
rsplinabscross
rsppolarizability
rspproperty
rspshg
rspthreepatransition
rsptpa
rsptpatransition
sadguessdriver
sanitychecks
scfdriver
scfgradientdriver
scfhessiandriver
scfrestdriver
scfrestopendriver
scfunrestdriver
seminario
shgdriver
smddriver
smdsolventproperties
solvationbuilder
solvationfepdriver
subcommunicators
submatrix
symmetryanalyzer
symmetryoperations
tdacppsolver
tdaeigensolver
tdaeigensolverunrest
tddftgradientdriver
tddftorbitalresponse
tdhfhessiandriver
threepatransitiondriver
tmparameters
tpadriver
tpafulldriver
tpareddriver
tpatransitiondriver
trajectorydriver
tsguesser
uffparameters
veloxchemlib
vibrationalanalysis
visualizationdriver
waterparameters
xtbdriver
xtbgradientdriver
xtbhessiandriver
VERSION
1.0rc4
FILE
/home/rocky/.conda/envs/vlxenv-dev/lib/python3.13/site-packages/veloxchem/__init__.py
Classes#
The functionality of VeloxChem is built into the classes it implements. An overview of the available classes is provided with the dir function.
dir(vlx)
['AODensityMatrix',
'Absorption',
'AtomBasis',
'AtomBdeDriver',
'AtomTypeIdentifier',
'BasisFunction',
'BlockDavidsonSolver',
'BlockedGtoPairBlock',
'C6',
'C6Driver',
'CircularDichroismSpectrum',
'ComplexResponse',
'ConformerGenerator',
'CpcmDriver',
'CphfSolver',
'CubicGrid',
'CubicResponseDriver',
'DensityViewer',
'DispersionModel',
'ElectricDipoleIntegralsDriver',
'ElectricDipoleMomentDriver',
'ElectricDipoleMomentGeom100Driver',
'EvbDataProcessing',
'EvbDriver',
'EvbFepDriver',
'EvbForceGroup',
'EvbReporter',
'EvbSystemBuilder',
'ExcitedStateAnalysisDriver',
'ExcitonModelDriver',
'FirstOrderProperties',
'FockDriver',
'FockGeom1000Driver',
'FockGeom1010Driver',
'FockGeom1100Driver',
'FockGeom2000Driver',
'GradientDriver',
'GridDriver',
'GtoBlock',
'GtoPairBlock',
'HessianDriver',
'HessianOrbitalResponse',
'IMDatabasePointCollecter',
'IMForceFieldGenerator',
'InputParser',
'InterpolationDatapoint',
'InterpolationDriver',
'KineticEnergyDriver',
'KineticEnergyGeom100Driver',
'KineticEnergyGeom101Driver',
'KineticEnergyGeom200Driver',
'LinearAbsorptionCrossSection',
'LinearResponseEigenSolver',
'LinearResponseSolver',
'LoPropDriver',
'MMDriver',
'MMForceFieldGenerator',
'MMGradientDriver',
'MOIntegralsDriver',
'Matrices',
'Matrix',
'MofBuilder',
'MolecularBasis',
'MolecularOrbitals',
'Molecule',
'Mp2Driver',
'MpiTask',
'NuclearPotentialDriver',
'NuclearPotentialErfDriver',
'NuclearPotentialErfGeom010Driver',
'NuclearPotentialErfGeom100Driver',
'NuclearPotentialGeom010Driver',
'NuclearPotentialGeom100Driver',
'NuclearPotentialGeom101Driver',
'NuclearPotentialGeom110Driver',
'NuclearPotentialGeom200Driver',
'NumerovDriver',
'OpenMMDriver',
'OpenMMDynamics',
'OpenMMGradientDriver',
'OptimizationDriver',
'OrbitalViewer',
'OutputStream',
'OverlapDriver',
'OverlapGeom100Driver',
'OverlapGeom101Driver',
'OverlapGeom200Driver',
'PEForceFieldGenerator',
'PolOrbitalResponse',
'Polarizability',
'PolarizabilityGradient',
'QuadraticResponseDriver',
'RIFockDriver',
'RIFockGradDriver',
'ReactionForceFieldBuilder',
'ReactionMatcher',
'RespChargesDriver',
'ResponseProperty',
'SHG',
'ScfGradientDriver',
'ScfHessianDriver',
'ScfRestrictedDriver',
'ScfRestrictedOpenDriver',
'ScfUnrestrictedDriver',
'Seminario',
'ShgDriver',
'SmdDriver',
'SolvationBuilder',
'SolvationFepDriver',
'SubCommunicators',
'SubMatrix',
'SymmetryAnalyzer',
'T3FlatBuffer',
'T4CScreener',
'TPA',
'TdaEigenSolver',
'TddftGradientDriver',
'TddftOrbitalResponse',
'TdhfHessianDriver',
'ThreeCenterElectronRepulsionDriver',
'ThreeCenterElectronRepulsionGeom010Driver',
'ThreeCenterElectronRepulsionGeom100Driver',
'ThreeCenterOverlapDriver',
'ThreePATransitionDriver',
'TpaFullDriver',
'TpaReducedDriver',
'TpaTransitionDriver',
'TransitionStateGuesser',
'TwoCenterElectronRepulsionDriver',
'TwoCenterElectronRepulsionGeom100Driver',
'VibrationalAnalysis',
'VisualizationDriver',
'XCFunctional',
'XCIntegrator',
'XCMolecularGradient',
'XtbDriver',
'XtbGradientDriver',
'XtbHessianDriver',
'__builtins__',
'__cached__',
'__doc__',
'__file__',
'__loader__',
'__name__',
'__package__',
'__path__',
'__spec__',
'__version__',
'aodensitymatrix',
'aoindices',
'assert_msg_critical',
'atombdedriver',
'atomtypeidentifier',
'available_functionals',
'available_pdft_functionals',
'batchsize',
'blockdavidson',
'bohr_in_angstrom',
'c2diis',
'c6driver',
'checkpoint',
'chemical_element_identifier',
'chemical_element_label',
'chemical_element_mass',
'chemical_element_max_angular_momentum',
'chemical_element_name',
'compute_angular_momentum_integrals',
'compute_electric_dipole_integrals',
'compute_kinetic_energy_integrals',
'compute_linear_momentum_integrals',
'compute_nuclear_potential_integrals',
'compute_overlap_integrals',
'configure_mkl_rt',
'conformergenerator',
'cpcmdriver',
'cphfsolver',
'cppsolver',
'cubicgrid',
'cubicresponsedriver',
'denmat',
'densityviewer',
'dftutils',
'dipole_in_debye',
'dispersionmodel',
'distributedarray',
'doubleresbeta',
'environment',
'errorhandler',
'evbdataprocessing',
'evbdriver',
'evbfepdriver',
'evbreporter',
'evbsystembuilder',
'excitedstateanalysisdriver',
'excitondriver',
'extinction_coefficient_from_beta',
'features',
'fine_structure_constant',
'firstorderprop',
'fockdriver',
'get_basis_path',
'get_data_path',
'gradientdriver',
'griddriver',
'hartree_in_ev',
'hartree_in_kcalpermol',
'hartree_in_kjpermol',
'hartree_in_wavenumber',
'hartree_in_wavenumbers',
'hessiandriver',
'hessianorbitalresponse',
'imdatabasepointcollecter',
'imforcefieldgenerator',
'inputparser',
'interpolationdatapoint',
'interpolationdriver',
'is_chemical_element',
'linearsolver',
'lreigensolver',
'lrsolver',
'make_matrices',
'make_matrix',
'mat_t',
'matrices',
'matrix',
'mklconf',
'mmdriver',
'mmforcefieldgenerator',
'mmgradientdriver',
'mofbuilder',
'mofmdprepare',
'mofoptimizer',
'mofpreparer',
'mofutils',
'mointsdriver',
'molecularbasis',
'molecularorbitals',
'molecule',
'molorb',
'mp2driver',
'mpi_master',
'mpitask',
'nonlinearsolver',
'numerovdriver',
'oneeints',
'openmmdriver',
'openmmdynamics',
'openmmgradientdriver',
'optimizationdriver',
'optimizationengine',
'orbitalviewer',
'outputstream',
'parse_xc_func',
'partition_atoms',
'peforcefieldgenerator',
'polarizabilitygradient',
'polorbitalresponse',
'print_features',
'profiler',
'pubchemfetcher',
'quadraticresponsedriver',
'reactionmatcher',
'read_results',
'reaffbuilder',
'respchargesdriver',
'rifockdriver',
'rotatory_strength_in_cgs',
'rspabsorption',
'rspc6',
'rspcdspec',
'rsplinabscross',
'rsppolarizability',
'rspproperty',
'rspshg',
'rsptpa',
'sadguessdriver',
'sanitychecks',
'scfdriver',
'scfgradientdriver',
'scfhessiandriver',
'scfrestdriver',
'scfrestopendriver',
'scfunrestdriver',
'seminario',
'set_omp_num_threads',
'set_vlxbasispath',
'set_vlxdatapath',
'shgdriver',
'smddriver',
'smdsolventproperties',
'solvationbuilder',
'solvationfepdriver',
'subcommunicators',
'symmetryanalyzer',
'symmetryoperations',
'tdacppsolver',
'tdaeigensolver',
'tddftgradientdriver',
'tddftorbitalresponse',
'tdhfhessiandriver',
'threepatransitiondriver',
'tmparameters',
'tpadriver',
'tpafulldriver',
'tpareddriver',
'tpatransitiondriver',
'tsguesser',
'uffparameters',
'veloxchemlib',
'vibrationalanalysis',
'visualizationdriver',
'waterparameters',
'xtbdriver',
'xtbgradientdriver',
'xtbhessiandriver']
Information about a specific class is available from the docstring.
print(vlx.ScfUnrestrictedDriver.__doc__)
Implements spin unrestricted open shell SCF method with C2-DIIS and
two-level C2-DIIS convergence accelerators.
:param comm:
The MPI communicator.
:param ostream:
The output stream.
Methods and properties#
The actual calculations are performed by the methods in the classes. To list the properties and methods of a class, the dir function can be used as follows.
dir(vlx.ScfRestrictedDriver)
['__class__',
'__deepcopy__',
'__delattr__',
'__dict__',
'__dir__',
'__doc__',
'__eq__',
'__firstlineno__',
'__format__',
'__ge__',
'__getattribute__',
'__getstate__',
'__gt__',
'__hash__',
'__init__',
'__init_subclass__',
'__le__',
'__lt__',
'__module__',
'__ne__',
'__new__',
'__reduce__',
'__reduce_ex__',
'__repr__',
'__setattr__',
'__sizeof__',
'__static_attributes__',
'__str__',
'__subclasshook__',
'__weakref__',
'_apply_mom',
'_check_convergence',
'_comp_2e_fock',
'_comp_2e_fock_single_comm',
'_comp_density_change',
'_comp_diis',
'_comp_energy',
'_comp_full_fock',
'_comp_gradient',
'_comp_npot_mat_parallel',
'_comp_number_of_electrons',
'_comp_one_ints',
'_delete_mos',
'_gen_molecular_orbitals',
'_get_acc_type',
'_get_dyn_threshold',
'_get_effective_fock',
'_get_guess_type',
'_get_scaled_fock',
'_get_scf_range',
'_graceful_exit',
'_need_graceful_exit',
'_print_energy_components',
'_print_ground_state',
'_print_header',
'_print_iter_data',
'_print_scf_energy',
'_print_scf_finish',
'_print_scf_title',
'_store_diis_data',
'_update_mol_orbs_phase',
'_write_final_hdf5',
'comm',
'compute',
'compute_s2',
'density',
'gen_initial_density_proj',
'gen_initial_density_restart',
'gen_initial_density_sad',
'get_scf_energy',
'get_scf_type_str',
'history',
'is_converged',
'maximum_overlap',
'mol_orbs',
'molecular_orbitals',
'nnodes',
'nodes',
'num_iter',
'ostream',
'print_attributes',
'print_keywords',
'rank',
'scf_energy',
'scf_results',
'scf_tensors',
'scf_type',
'set_start_orbitals',
'update_settings',
'validate_checkpoint',
'write_checkpoint']