#!/usr/bin/env python
# Copyright 2014-2020 The PySCF Developers. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Author: Qiming Sun <osirpt.sun@gmail.com>
#
'''
Hartree-Fock
============
Simple usage::
>>> from pyscf import gto, scf
>>> mol = gto.M(atom='H 0 0 0; H 0 0 1')
>>> mf = scf.RHF(mol).run()
:func:`scf.RHF` returns an instance of SCF class. There are some parameters
to control the SCF method.
verbose : int
Print level. Default value equals to :class:`Mole.verbose`
max_memory : float or int
Allowed memory in MB. Default value equals to :class:`Mole.max_memory`
chkfile : str
checkpoint file to save MOs, orbital energies etc.
conv_tol : float
converge threshold. Default is 1e-10
max_cycle : int
max number of iterations. Default is 50
init_guess : str
initial guess method. It can be one of 'minao', 'atom', '1e', 'chkfile'.
Default is 'minao'
DIIS : class listed in :mod:`scf.diis`
Default is :class:`diis.SCF_DIIS`. Set it to None/False to turn off DIIS.
diis : bool
whether to do DIIS. Default is True.
diis_space : int
DIIS space size. By default, 8 Fock matrices and errors vector are stored.
diis_start_cycle : int
The step to start DIIS. Default is 0.
level_shift_factor : float or int
Level shift (in AU) for virtual space. Default is 0.
direct_scf : bool
Direct SCF is used by default.
direct_scf_tol : float
Direct SCF cutoff threshold. Default is 1e-13.
callback : function
callback function takes one dict as the argument which is
generated by the builtin function :func:`locals`, so that the
callback function can access all local variables in the current
environment.
conv_check : bool
An extra cycle to check convergence after SCF iterations.
nelec : (int,int), for UHF/ROHF class
freeze the number of (alpha,beta) electrons.
irrep_nelec : dict, for symmetry- RHF/ROHF/UHF class only
to indicate the number of electrons for each irreps.
In RHF, give {'ir_name':int, ...} ;
In ROHF/UHF, give {'ir_name':(int,int), ...} .
It is effective when :attr:`Mole.symmetry` is set ``True``.
auxbasis : str, for density fitting SCF only
Auxiliary basis for density fitting.
>>> mf = scf.density_fit(scf.UHF(mol))
>>> mf.scf()
Density fitting can be applied to all non-relativistic HF class.
with_ssss : bool, for Dirac-Hartree-Fock only
If False, ignore small component integrals (SS|SS). Default is True.
with_gaunt : bool, for Dirac-Hartree-Fock only
If False, ignore Gaunt interaction. Default is False.
Saved results
converged : bool
SCF converged or not
e_tot : float
Total HF energy (electronic energy plus nuclear repulsion)
mo_energy :
Orbital energies
mo_occ
Orbital occupancy
mo_coeff
Orbital coefficients
'''
from pyscf import gto
from pyscf.scf import hf
rhf = hf
from pyscf.scf import rohf
from pyscf.scf import hf_symm
rhf_symm = hf_symm
from pyscf.scf import uhf
from pyscf.scf import uhf_symm
from pyscf.scf import ghf
from pyscf.scf import ghf_symm
from pyscf.scf import dhf
from pyscf.scf import chkfile
from pyscf.scf import addons
from pyscf.scf import diis
from pyscf.scf import dispersion
from pyscf.scf.diis import DIIS, CDIIS, EDIIS, ADIIS
from pyscf.scf.uhf import spin_square
from pyscf.scf.hf import get_init_guess
from pyscf.scf.addons import *
[docs]
def HF(mol, *args):
if mol.nelectron == 1 or mol.spin == 0:
return RHF(mol, *args)
else:
return UHF(mol, *args)
HF.__doc__ = '''
A wrap function to create SCF class (RHF or UHF).\n
''' + hf.SCF.__doc__
gto.Mole.HF = property(HF)
[docs]
def RHF(mol, *args):
if mol.spin == 0:
if not mol.symmetry or mol.groupname == 'C1':
return rhf.RHF(mol, *args)
else:
return rhf_symm.RHF(mol, *args)
else:
return ROHF(mol, *args)
RHF.__doc__ = hf.RHF.__doc__
gto.Mole.RHF = property(RHF)
[docs]
def ROHF(mol, *args):
if mol.nelectron == 1:
if not mol.symmetry or mol.groupname == 'C1':
return rohf.HF1e(mol)
else:
return hf_symm.HF1e(mol, *args)
elif not mol.symmetry or mol.groupname == 'C1':
return rohf.ROHF(mol, *args)
else:
return hf_symm.ROHF(mol, *args)
ROHF.__doc__ = rohf.ROHF.__doc__
gto.Mole.ROHF = property(ROHF)
[docs]
def UHF(mol, *args):
if mol.nelectron == 1:
if not mol.symmetry or mol.groupname == 'C1':
return uhf.HF1e(mol, *args)
else:
return uhf_symm.HF1e(mol, *args)
elif not mol.symmetry or mol.groupname == 'C1':
return uhf.UHF(mol, *args)
else:
return uhf_symm.UHF(mol, *args)
UHF.__doc__ = uhf.UHF.__doc__
gto.Mole.UHF = property(UHF)
[docs]
def GHF(mol, *args):
if mol.nelectron == 1:
if not mol.symmetry or mol.groupname == 'C1':
return ghf.HF1e(mol)
else:
return ghf_symm.HF1e(mol, *args)
elif not mol.symmetry or mol.groupname == 'C1':
return ghf.GHF(mol, *args)
else:
return ghf_symm.GHF(mol, *args)
GHF.__doc__ = ghf.GHF.__doc__
gto.Mole.GHF = property(GHF)
[docs]
def DHF(mol, *args):
if mol.nelectron == 1:
return dhf.HF1e(mol)
elif dhf.zquatev and mol.spin == 0:
return dhf.RDHF(mol, *args)
else:
return dhf.DHF(mol, *args)
DHF.__doc__ = dhf.DHF.__doc__
gto.Mole.DHF = property(DHF)
[docs]
def X2C(mol, *args):
'''X2C Hartree-Fock'''
from pyscf.x2c import x2c
if dhf.zquatev and mol.spin == 0:
return x2c.RHF(mol, *args)
else:
return x2c.UHF(mol, *args)
gto.Mole.X2C = gto.Mole.X2C_HF = property(X2C)
[docs]
def sfx2c1e(mf):
'''spin-free (the scalar part) X2C with 1-electron X-matrix'''
return mf.sfx2c1e()
sfx2c = sfx2c1e
[docs]
def density_fit(mf, auxbasis=None, with_df=None, only_dfj=False):
return mf.density_fit(auxbasis, with_df, only_dfj)
[docs]
def newton(mf):
from pyscf.soscf import newton_ah
return newton_ah.newton(mf)
fast_newton = addons.fast_newton
[docs]
def KS(mol, *args):
from pyscf import dft
return dft.KS(mol, *args)
[docs]
def RKS(mol, *args):
from pyscf import dft
return dft.RKS(mol, *args)
[docs]
def ROKS(mol, *args):
from pyscf import dft
return dft.ROKS(mol, *args)
[docs]
def UKS(mol, *args):
from pyscf import dft
return dft.UKS(mol, *args)
[docs]
def GKS(mol, *args):
from pyscf import dft
return dft.GKS(mol, *args)
[docs]
def DKS(mol, *args):
from pyscf import dft
return dft.DKS(mol, *args)