def ccsd(self, t1=None, t2=None, eris=None, mbpt2=False):
'''Ground-state unrestricted (U)CCSD.
Kwargs:
mbpt2 : bool
Use one-shot MBPT2 approximation to CCSD.
'''
if mbpt2:
from pyscf.mp import gmp2
pt = gmp2.GMP2(self._scf, self.frozen, self.mo_coeff, self.mo_occ)
self.e_corr, self.t2 = pt.kernel(eris=eris)
nocc, nvir = self.t2.shape[1:3]
self.t1 = np.zeros((nocc,nvir))
return self.e_corr, self.t1, self.t2
# Initialize orbspin so that we can attach it to t1, t2
if getattr(self.mo_coeff, 'orbspin', None) is None:
orbspin = scf.ghf.guess_orbspin(self.mo_coeff)
if not np.any(orbspin == -1):
self.mo_coeff = lib.tag_array(self.mo_coeff, orbspin=orbspin)
e_corr, self.t1, self.t2 = ccsd.CCSD.ccsd(self, t1, t2, eris)
if getattr(eris, 'orbspin', None) is not None:
self.t1 = lib.tag_array(self.t1, orbspin=eris.orbspin)
self.t2 = lib.tag_array(self.t2, orbspin=eris.orbspin)
return e_corr, self.t1, self.t2
def GMP2(mf, frozen=0, mo_coeff=None, mo_occ=None):
__doc__ = gmp2.GMP2.__doc__
from pyscf.soscf import newton_ah
if isinstance(mf, newton_ah._CIAH_SOSCF) or not isinstance(mf, scf.ghf.GHF):
mf = mf.to_ghf()
if getattr(mf, 'with_df', None):
raise NotImplementedError('DF-GMP2')
else:
return gmp2.GMP2(mf, frozen, mo_coeff, mo_occ)
def GMP2(mf, frozen=None, mo_coeff=None, mo_occ=None):
from pyscf.soscf import newton_ah
if isinstance(mf,
newton_ah._CIAH_SOSCF) or not isinstance(mf, scf.ghf.GHF):
mf = mf.to_ghf()
if getattr(mf, 'with_df', None):
return dfgmp2.DFGMP2(mf, frozen, mo_coeff, mo_occ)
else:
return gmp2.GMP2(mf, frozen, mo_coeff, mo_occ)
def GMP2(mf, frozen=0, mo_coeff=None, mo_occ=None):
__doc__ = gmp2.GMP2.__doc__
from pyscf.soscf import newton_ah
if isinstance(mf,
newton_ah._CIAH_SOSCF) or not isinstance(mf, scf.ghf.GHF):
mf = scf.addons.convert_to_ghf(mf)
if hasattr(mf, 'with_df') and mf.with_df:
raise NotImplementedError('DF-GMP2')
else:
return gmp2.GMP2(mf, frozen, mo_coeff, mo_occ)