def ao2mo(self, mo_coeff=None):
nmo = self.nmo
nao = self.mo_coeff.shape[0]
nmo_pair = nmo * (nmo+1) // 2
nao_pair = nao * (nao+1) // 2
mem_incore = (max(nao_pair**2, nmo**4) + nmo_pair**2) * 8/1e6
mem_now = lib.current_memory()[0]
if (self._scf._eri is not None and
(mem_incore+mem_now < self.max_memory) or self.mol.incore_anyway):
return ccsd._make_eris_incore(self, mo_coeff)
if getattr(self._scf, 'with_df', None):
logger.warn(self, 'CISD detected DF being used in the HF object. '
'MO integrals are computed based on the DF 3-index tensors.\n'
'It\'s recommended to use dfccsd.CCSD for the '
'DF-CISD calculations')
return ccsd._make_df_eris_outcore(self, mo_coeff)
return ccsd._make_eris_outcore(self, mo_coeff)
if __name__ == '__main__':
from pyscf import gto
from pyscf import ao2mo
mol = gto.Mole()
mol.verbose = 0
mol.atom = [
['O', (0., 0., 0.)],
['H', (0., -0.757, 0.587)],
['H', (0., 0.757, 0.587)],
]
mol.basis = 'sto3g'
mol.build()
mf = scf.RHF(mol).run()
myci = CISD(mf)
eris = ccsd._make_eris_outcore(myci, mf.mo_coeff)
ecisd, civec = myci.kernel(eris=eris)
print(ecisd - -0.048878084082066106)
nmo = myci.nmo
nocc = myci.nocc
rdm1 = myci.make_rdm1(civec)
rdm2 = myci.make_rdm2(civec)
h1e = reduce(numpy.dot, (mf.mo_coeff.T, mf.get_hcore(), mf.mo_coeff))
h2e = ao2mo.kernel(mf._eri, mf.mo_coeff)
h2e = ao2mo.restore(1, h2e, nmo)
e2 = (numpy.einsum('ij,ji', h1e, rdm1) +
numpy.einsum('ijkl,ijkl', h2e, rdm2) * .5)
print(ecisd + mf.e_tot - mol.energy_nuc() - e2) # = 0
print(
