Source code for pyscf.pbc.scf.addons

#!/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>
#         Timothy Berkelbach <tim.berkelbach@gmail.com>
#

from functools import reduce
import numpy
import scipy.linalg
import scipy.special
import scipy.optimize
from pyscf import lib
from pyscf.pbc import gto as pbcgto
from pyscf.pbc import tools
from pyscf.lib import logger
from pyscf.scf import addons as mol_addons
from pyscf.pbc.lib.kpts import KPoints
from pyscf.pbc.tools import k2gamma
from pyscf import __config__

SMEARING_METHOD = mol_addons.SMEARING_METHOD


[docs] def project_mo_nr2nr(cell1, mo1, cell2, kpts=None): r''' Project orbital coefficients .. math:: |\psi1> = |AO1> C1 |\psi2> = P |\psi1> = |AO2>S^{-1}<AO2| AO1> C1 = |AO2> C2 C2 = S^{-1}<AO2|AO1> C1 ''' s22 = cell2.pbc_intor('int1e_ovlp', hermi=1, kpts=kpts) s21 = pbcgto.intor_cross('int1e_ovlp', cell2, cell1, kpts=kpts) if kpts is None or numpy.shape(kpts) == (3,): # A single k-point return scipy.linalg.solve(s22, s21.dot(mo1), assume_a='pos') else: assert (len(kpts) == len(mo1)) return [scipy.linalg.solve(s22[k], s21[k].dot(mo1[k]), assume_a='pos') for k, kpt in enumerate(kpts)]
[docs] def project_dm_k2k(cell, dm, kpts1, kpts2): '''Project density matrix from k-point mesh 1 to k-point mesh 2''' bvk_mesh = k2gamma.kpts_to_kmesh(cell, kpts1) Ls = k2gamma.translation_vectors_for_kmesh(cell, bvk_mesh, True) c = _k2k_projection(kpts1, kpts2, Ls) return lib.einsum('km,kuv->muv', c, dm)
def _k2k_projection(kpts1, kpts2, Ls): weight = 1. / len(Ls) expRk1 = numpy.exp(1j*numpy.dot(Ls, kpts1.T)) expRk2 = numpy.exp(-1j*numpy.dot(Ls, kpts2.T)) c = expRk1.T.dot(expRk2) * weight return (c*c.conj()).real.copy() def _partition_occ(mo_occ, mo_energy_kpts): mo_occ_kpts = [] p1 = 0 for e in mo_energy_kpts: p0, p1 = p1, p1 + e.size occ = mo_occ[p0:p1] mo_occ_kpts.append(occ) return mo_occ_kpts def _get_grad_tril(mo_coeff_kpts, mo_occ_kpts, fock): grad_kpts = [] for k, mo in enumerate(mo_coeff_kpts): f_mo = reduce(numpy.dot, (mo.T.conj(), fock[k], mo)) nmo = f_mo.shape[0] grad_kpts.append(f_mo[numpy.tril_indices(nmo, -1)]) return numpy.hstack(grad_kpts) class _SmearingKSCF(mol_addons._SmearingSCF): def get_occ(self, mo_energy_kpts=None, mo_coeff_kpts=None): '''Label the occupancies for each orbital for sampled k-points. This is a k-point version of scf.hf.SCF.get_occ ''' from pyscf.pbc import scf if (self.sigma == 0) or (not self.sigma) or (not self.smearing_method): mo_occ_kpts = super().get_occ(mo_energy_kpts, mo_coeff_kpts) return mo_occ_kpts is_uhf = self.istype('KUHF') is_rhf = self.istype('KRHF') if isinstance(self, scf.krohf.KROHF): # ROHF leads to two Fock matrices. It's not clear how to define the # Roothaan effective Fock matrix from the two. raise NotImplementedError('Smearing-ROHF') sigma = self.sigma if self.smearing_method.lower() == 'fermi': f_occ = mol_addons._fermi_smearing_occ else: f_occ = mol_addons._gaussian_smearing_occ kpts = getattr(self, 'kpts', None) if isinstance(kpts, KPoints): nkpts = kpts.nkpts mo_energy_kpts = kpts.transform_mo_energy(mo_energy_kpts) else: nkpts = len(kpts) if self.fix_spin and is_uhf: # spin separated fermi level mo_es = [numpy.hstack(mo_energy_kpts[0]), numpy.hstack(mo_energy_kpts[1])] nocc = self.nelec if self.mu0 is None: mu_a, occa = mol_addons._smearing_optimize(f_occ, mo_es[0], nocc[0], sigma) mu_b, occb = mol_addons._smearing_optimize(f_occ, mo_es[1], nocc[1], sigma) else: if numpy.isscalar(self.mu0): mu_a = mu_b = self.mu0 elif len(self.mu0) == 2: mu_a, mu_b = self.mu0 else: raise TypeError(f'Unsupported mu0: {self.mu0}') occa = f_occ(mu_a, mo_es[0], sigma) occb = f_occ(mu_b, mo_es[1], sigma) mu = [mu_a, mu_b] mo_occs = [occa, occb] self.entropy = self._get_entropy(mo_es[0], mo_occs[0], mu[0]) self.entropy += self._get_entropy(mo_es[1], mo_occs[1], mu[1]) self.entropy /= nkpts fermi = (mol_addons._get_fermi(mo_es[0], nocc[0]), mol_addons._get_fermi(mo_es[1], nocc[1])) logger.debug(self, ' Alpha-spin Fermi level %g Sum mo_occ_kpts = %s should equal nelec = %s', fermi[0], mo_occs[0].sum(), nocc[0]) logger.debug(self, ' Beta-spin Fermi level %g Sum mo_occ_kpts = %s should equal nelec = %s', fermi[1], mo_occs[1].sum(), nocc[1]) logger.info(self, ' sigma = %g Optimized mu_alpha = %.12g entropy = %.12g', sigma, mu[0], self.entropy) logger.info(self, ' sigma = %g Optimized mu_beta = %.12g entropy = %.12g', sigma, mu[1], self.entropy) mo_occ_kpts =(_partition_occ(mo_occs[0], mo_energy_kpts[0]), _partition_occ(mo_occs[1], mo_energy_kpts[1])) tools.print_mo_energy_occ_kpts(self, mo_energy_kpts, mo_occ_kpts, True) else: nocc = nelectron = self.mol.tot_electrons(nkpts) if is_uhf: mo_es_a = numpy.hstack(mo_energy_kpts[0]) mo_es_b = numpy.hstack(mo_energy_kpts[1]) mo_es = numpy.append(mo_es_a, mo_es_b) else: mo_es = numpy.hstack(mo_energy_kpts) if is_rhf: nocc = (nelectron + 1) // 2 if self.mu0 is None: mu, mo_occs = mol_addons._smearing_optimize(f_occ, mo_es, nocc, sigma) else: # If mu0 is given, fix mu instead of electron number. XXX -Chong Sun mu = self.mu0 assert numpy.isscalar(mu) mo_occs = f_occ(mu, mo_es, sigma) self.entropy = self._get_entropy(mo_es, mo_occs, mu) / nkpts if is_rhf: mo_occs *= 2 self.entropy *= 2 fermi = mol_addons._get_fermi(mo_es, nocc) logger.debug(self, ' Fermi level %g Sum mo_occ_kpts = %s should equal nelec = %s', fermi, mo_occs.sum(), nelectron) logger.info(self, ' sigma = %g Optimized mu = %.12g entropy = %.12g', sigma, mu, self.entropy) if is_uhf: # mo_es_a and mo_es_b may have different dimensions for # different k-points nmo_a = mo_es_a.size mo_occ_kpts =(_partition_occ(mo_occs[:nmo_a], mo_energy_kpts[0]), _partition_occ(mo_occs[nmo_a:], mo_energy_kpts[1])) else: mo_occ_kpts = _partition_occ(mo_occs, mo_energy_kpts) tools.print_mo_energy_occ_kpts(self, mo_energy_kpts, mo_occ_kpts, is_uhf) if isinstance(kpts, KPoints): if is_uhf: mo_occ_kpts = (kpts.check_mo_occ_symmetry(mo_occ_kpts[0]), kpts.check_mo_occ_symmetry(mo_occ_kpts[1])) else: mo_occ_kpts = kpts.check_mo_occ_symmetry(mo_occ_kpts) return mo_occ_kpts def get_grad(self, mo_coeff_kpts, mo_occ_kpts, fock=None): if (self.sigma == 0) or (not self.sigma) or (not self.smearing_method): return super().get_grad(mo_coeff_kpts, mo_occ_kpts, fock) if fock is None: dm1 = self.make_rdm1(mo_coeff_kpts, mo_occ_kpts) fock = self.get_hcore() + self.get_veff(self.mol, dm1) if self.istype('KUHF'): ga = _get_grad_tril(mo_coeff_kpts[0], mo_occ_kpts[0], fock[0]) gb = _get_grad_tril(mo_coeff_kpts[1], mo_occ_kpts[1], fock[1]) return numpy.hstack((ga,gb)) else: # rhf and ghf return _get_grad_tril(mo_coeff_kpts, mo_occ_kpts, fock)
[docs] def smearing(mf, sigma=None, method=SMEARING_METHOD, mu0=None, fix_spin=False): '''Fermi-Dirac or Gaussian smearing''' from pyscf.pbc.scf import khf if not isinstance(mf, khf.KSCF): return mol_addons.smearing(mf, sigma, method, mu0, fix_spin) if isinstance(mf, mol_addons._SmearingSCF): mf.sigma = sigma mf.smearing_method = method mf.mu0 = mu0 mf.fix_spin = fix_spin return mf return lib.set_class(_SmearingKSCF(mf, sigma, method, mu0, fix_spin), (_SmearingKSCF, mf.__class__))
[docs] def smearing_(mf, *args, **kwargs): mf1 = smearing(mf, *args, **kwargs) mf.__class__ = mf1.__class__ mf.__dict__ = mf1.__dict__ return mf
[docs] def canonical_occ_(mf, nelec=None): '''Label the occupancies for each orbital for sampled k-points. This is for KUHF objects. Each k-point has a fixed number of up and down electrons in this, which results in a finite size error for metallic systems but can accelerate convergence. ''' from pyscf.pbc.scf import kuhf assert (isinstance(mf, kuhf.KUHF)) def get_occ(mo_energy_kpts=None, mo_coeff=None): if mo_energy_kpts is None: mo_energy_kpts = mf.mo_energy if nelec is None: cell_nelec = mf.cell.nelec else: cell_nelec = nelec homo=[-1e8,-1e8] lumo=[1e8,1e8] mo_occ_kpts = [[], []] for s in [0,1]: for k, mo_energy in enumerate(mo_energy_kpts[s]): e_idx = numpy.argsort(mo_energy) e_sort = mo_energy[e_idx] n = cell_nelec[s] mo_occ = numpy.zeros_like(mo_energy) mo_occ[e_idx[:n]] = 1 homo[s] = max(homo[s], e_sort[n-1]) lumo[s] = min(lumo[s], e_sort[n]) mo_occ_kpts[s].append(mo_occ) for nm,s in zip(['alpha','beta'],[0,1]): logger.info(mf, nm+' HOMO = %.12g LUMO = %.12g', homo[s], lumo[s]) if homo[s] > lumo[s]: logger.warn(mf, "WARNING! HOMO is greater than LUMO! " "This may lead to incorrect canonical occupation.") return mo_occ_kpts mf.get_occ = get_occ return mf
canonical_occ = canonical_occ_
[docs] def convert_to_uhf(mf, out=None): '''Convert the given mean-field object to the corresponding unrestricted HF/KS object ''' from pyscf.pbc import scf from pyscf.pbc import dft if out is None: if isinstance(mf, (scf.uhf.UHF, scf.kuhf.KUHF)): return mf.copy() else: if isinstance(mf, (scf.ghf.GHF, scf.kghf.KGHF)): raise NotImplementedError( f'No conversion from {mf.__class__} to uhf object') known_cls = { dft.krks_ksymm.KRKS : dft.kuks_ksymm.KUKS, dft.kroks.KROKS: dft.kuks.KUKS, dft.krks.KRKS : dft.kuks.KUKS, dft.roks.ROKS : dft.uks.UKS , dft.rks.RKS : dft.uks.UKS , scf.khf_ksymm.KRHF : scf.kuhf_ksymm.KUHF, scf.krohf.KROHF: scf.kuhf.KUHF, scf.khf.KRHF : scf.kuhf.KUHF, scf.rohf.ROHF : scf.uhf.UHF , scf.hf.RHF : scf.uhf.UHF , } # .with_df should never be removed or changed during the conversion. # It is needed to compute JK matrix in all pbc SCF objects out = mol_addons._object_without_soscf(mf, known_cls, False) else: assert (isinstance(out, (scf.uhf.UHF, scf.kuhf.KUHF))) if isinstance(mf, scf.khf.KSCF): assert (isinstance(out, scf.khf.KSCF)) else: assert (not isinstance(out, scf.khf.KSCF)) if out is not None: out = mol_addons._update_mf_without_soscf(mf, out, False) return mol_addons._update_mo_to_uhf_(mf, out)
[docs] def convert_to_rhf(mf, out=None): '''Convert the given mean-field object to the corresponding restricted HF/KS object ''' from pyscf.pbc import scf from pyscf.pbc import dft if getattr(mf, 'nelec', None) is None: nelec = mf.cell.nelec else: nelec = mf.nelec if out is not None: assert (isinstance(out, (scf.hf.RHF, scf.khf.KRHF))) if isinstance(mf, scf.khf.KSCF): assert (isinstance(out, scf.khf.KSCF)) else: assert (not isinstance(out, scf.khf.KSCF)) out = mol_addons._update_mf_without_soscf(mf, out, False) elif nelec[0] != nelec[1] and isinstance(mf, (scf.rohf.ROHF, scf.krohf.KROHF)): if getattr(mf, '_scf', None): return mol_addons._update_mf_without_soscf(mf, mf._scf.copy(), False) else: return mf.copy() else: if isinstance(mf, (scf.hf.RHF, scf.khf.KRHF)): return mf.copy() else: if isinstance(mf, (scf.ghf.GHF, scf.kghf.KGHF)): raise NotImplementedError( f'No conversion from {mf.__class__} to rhf object') if nelec[0] == nelec[1]: known_cls = { dft.kuks_ksymm.KUKS : dft.krks_ksymm.KRKS, dft.kuks.KUKS : dft.krks.KRKS , dft.kroks.KROKS : dft.krks.KRKS , dft.uks.UKS : dft.rks.RKS , dft.roks.ROKS : dft.rks.RKS , scf.kuhf_ksymm.KUHF : scf.khf_ksymm.KRHF , scf.kuhf.KUHF : scf.khf.KRHF , scf.krohf.KROHF : scf.khf.KRHF , scf.uhf.UHF : scf.hf.RHF , scf.rohf.ROHF : scf.hf.RHF , } else: known_cls = { dft.kuks.KUKS : dft.kroks.KROKS, dft.uks.UKS : dft.roks.ROKS , scf.kuhf.KUHF : scf.krohf.KROHF, scf.uhf.UHF : scf.rohf.ROHF , } # .with_df should never be removed or changed during the conversion. # It is needed to compute JK matrix in all pbc SCF objects out = mol_addons._object_without_soscf(mf, known_cls, False) return mol_addons._update_mo_to_rhf_(mf, out)
[docs] def convert_to_ghf(mf, out=None): '''Convert the given mean-field object to the generalized HF/KS object Args: mf : SCF object Returns: An generalized SCF object ''' from pyscf.pbc import scf if out is not None: assert (isinstance(out, (scf.ghf.GHF, scf.kghf.KGHF))) if isinstance(mf, scf.khf.KSCF): assert (isinstance(out, scf.khf.KSCF)) else: assert (not isinstance(out, scf.khf.KSCF)) if isinstance(mf, (scf.ghf.GHF, scf.kghf.KGHF)): if out is None: return mf.copy() else: out.__dict__.update(mf.__dict__) return out elif isinstance(mf, scf.khf.KSCF): def update_mo_(mf, mf1): mf1.__dict__.update(mf.__dict__) if mf.mo_energy is not None: mf1.mo_energy = [] mf1.mo_occ = [] mf1.mo_coeff = [] if hasattr(mf.kpts, 'nkpts_ibz'): nkpts = mf.kpts.nkpts_ibz else: nkpts = len(mf.kpts) is_rhf = mf.istype('KRHF') for k in range(nkpts): if is_rhf: mo_a = mo_b = mf.mo_coeff[k] ea = getattr(mf.mo_energy[k], 'mo_ea', mf.mo_energy[k]) eb = getattr(mf.mo_energy[k], 'mo_eb', mf.mo_energy[k]) occa = mf.mo_occ[k] > 0 occb = mf.mo_occ[k] == 2 orbspin = mol_addons.get_ghf_orbspin(ea, mf.mo_occ[k], True) else: mo_a = mf.mo_coeff[0][k] mo_b = mf.mo_coeff[1][k] ea = mf.mo_energy[0][k] eb = mf.mo_energy[1][k] occa = mf.mo_occ[0][k] occb = mf.mo_occ[1][k] orbspin = mol_addons.get_ghf_orbspin((ea, eb), (occa, occb), False) nao, nmo = mo_a.shape mo_energy = numpy.empty(nmo*2) mo_energy[orbspin==0] = ea mo_energy[orbspin==1] = eb mo_occ = numpy.empty(nmo*2) mo_occ[orbspin==0] = occa mo_occ[orbspin==1] = occb mo_coeff = numpy.zeros((nao*2,nmo*2), dtype=mo_a.dtype) mo_coeff[:nao,orbspin==0] = mo_a mo_coeff[nao:,orbspin==1] = mo_b mo_coeff = lib.tag_array(mo_coeff, orbspin=orbspin) mf1.mo_energy.append(mo_energy) mf1.mo_occ.append(mo_occ) mf1.mo_coeff.append(mo_coeff) return mf1 if out is None: out = scf.kghf.KGHF(mf.cell) return update_mo_(mf, out) else: if out is None: out = scf.ghf.GHF(mf.cell) out = mol_addons.convert_to_ghf(mf, out, remove_df=False) # Manually update .with_df because this attribute may not be passed to the # output object correctly in molecular convert function out.with_df = mf.with_df return out
[docs] def convert_to_kscf(mf, out=None): '''Convert gamma point SCF object to k-point SCF object ''' from pyscf.pbc import scf, dft if not isinstance(mf, scf.khf.KSCF): assert isinstance(mf, scf.hf.SCF) known_cls = { dft.uks.UKS : dft.kuks.KUKS , dft.roks.ROKS : dft.kroks.KROKS, dft.rks.RKS : dft.krks.KRKS , dft.gks.GKS : dft.kgks.KGKS , scf.uhf.UHF : scf.kuhf.KUHF , scf.rohf.ROHF : scf.krohf.KROHF, scf.hf.RHF : scf.khf.KRHF , scf.ghf.GHF : scf.kghf.KGHF , } mf = mol_addons._object_without_soscf(mf, known_cls, False) if mf.mo_energy is not None: if isinstance(mf, scf.kuhf.KUHF): mf.mo_occ = mf.mo_occ[:, numpy.newaxis] mf.mo_coeff = mf.mo_coeff[:, numpy.newaxis] mf.mo_energy = mf.mo_energy[:, numpy.newaxis] else: mf.mo_occ = mf.mo_occ[numpy.newaxis] mf.mo_coeff = mf.mo_coeff[numpy.newaxis] mf.mo_energy = mf.mo_energy[numpy.newaxis] if hasattr(mf, '_numint'): kpts = getattr(mf.kpts, 'kpts', mf.kpts) mf._numint = dft.numint.KNumInt(kpts) if out is None: return mf return mol_addons._update_mf_without_soscf(mf, out, False)
convert_to_khf = convert_to_kscf
[docs] def mo_energy_with_exxdiv_none(mf, mo_coeff=None): ''' compute mo energy from the diagonal of fock matrix with exxdiv=None ''' from pyscf.pbc import scf, dft from pyscf.lib import logger log = logger.new_logger(mf) if mo_coeff is None: mo_coeff = mf.mo_coeff if mf.exxdiv is None and mf.mo_coeff is mo_coeff: return mf.mo_energy with lib.temporary_env(mf, exxdiv=None): dm = mf.make_rdm1(mo_coeff) vhf = mf.get_veff(mf.mol, dm) fockao = mf.get_fock(vhf=vhf, dm=dm) def _get_moe1(C, fao): return lib.einsum('pi,pq,qi->i', C.conj(), fao, C).real def _get_moek(kC, kfao): return [_get_moe1(C, fao) for C,fao in zip(kC, kfao)] # avoid using isinstance as some are other's derived class if mf.__class__ in [scf.rhf.RHF, scf.ghf.GHF, dft.rks.RKS, dft.gks.GKS]: return _get_moe1(mo_coeff, fockao) elif mf.__class__ in [scf.uhf.UHF, dft.uks.UKS]: return _get_moek(mo_coeff, fockao) elif mf.__class__ in [scf.krhf.KRHF, scf.kghf.KGHF, dft.krks.KRKS, dft.kgks.KGKS]: return _get_moek(mo_coeff, fockao) elif mf.__class__ in [scf.kuhf.KUHF, dft.kuks.KUKS]: return [_get_moek(kC, kfao) for kC,kfao in zip(mo_coeff,fockao)] else: log.error(f'Unknown SCF type {mf.__class__.__name__}') raise NotImplementedError