Reference states#
A detailed list of keyword can be found in the SCF optimization section of the input file keywords page.
By default, the Hartree–Fock method is employed. To use Kohn–Sham DFT, any of the several available functionals is specified as illustrated below, see the exchange-correlation functionals page for a complete list of available functionals.
Restricted closed-shell#
Python script
import veloxchem as vlx
mol_xyz_string = """
...
"""
molecule = vlx.Molecule.read_xyz_string(mol_xyz_string)
basis = vlx.MolecularBasis.read(molecule, 'def2-svp')
scfdrv = vlx.ScfRestrictedDriver()
scfdrv.filename = 'mol-scf'
scf_results = scfdrv.compute(molecule, basis)
Download a Python script type of input file to perfom a restricted closed-shell calculation for the biphenyl molecule at the HF/def2-svp level of theory.
Text file
@jobs
task: scf
@end
@method settings
basis: def2-svp
@end
@molecule
charge: 0
multiplicity: 1
xyz:
...
@end
Download a text format type of input file to perfom a restricted closed-shell calculation for the biphenyl molecule at the HF/def2-svp level of theory.
Restricted open-shell#
Python script
import veloxchem as vlx
mol_xyz_string = """
...
"""
molecule = vlx.Molecule.read_xyz_string(mol_xyz_string)
molecule.set_multiplicity(2)
basis = vlx.MolecularBasis.read(molecule, '6-31+G*')
scfdrv = vlx.ScfRestrictedOpenDriver()
scfdrv.filename = 'mol-roscf'
scfdrv.xcfun = 'b3lyp'
scf_results = scfdrv.compute(molecule, basis)
Download a Python script type of input file to perfom a restricted open-shell calculation for the tempo molecule at the B3LYP/6-31+G* level of theory.
Text file
@jobs
task: roscf
@end
@method settings
basis: 6-31+G*
xcfun: b3lyp
@end
@molecule
charge: 1
multiplicity: 2
xyz:
...
@end
Download a text format type of input file to perfom a restricted open-shell calculation for the tempo molecule at the B3LYP/6-31+G* level of theory.
Unrestricted open-shell#
Python script
import veloxchem as vlx
mol_xyz_string = """
...
"""
molecule = vlx.Molecule.read_xyz_string(mol_xyz_string)
molecule.set_multiplicity(2)
basis = vlx.MolecularBasis.read(molecule, 'CC-PVDZ')
scfdrv = vlx.ScfUnrestrictedDriver()
scfdrv.filename = 'mol-uscf'
scfdrv.xcfun = 'b3lyp'
scf_results = scfdrv.compute(molecule, basis)
Download a Python script type of input file to perfom a unrestricted open-shell calculation for the triphenylmethyl radical molecule (also called trityl radical) at the PBE0/CC-PVDZ level of theory.
Text file
@jobs
task: uscf
@end
@method settings
basis: CC-PVDZ
xcfun: PBE0
@end
@molecule
charge: 1
multiplicity: 2
xyz:
...
@end
Download a text format type of input file to perfom a unrestricted open-shell calculation for the triphenylmethyl radical molecule (also called trityl radical) at the PBE0/CC-PVDZ level of theory.
