dft_zmp/n2v.patched/engines/psi4.py
2024-02-26 10:44:51 +01:00

193 lines
6.8 KiB
Python
Executable file

"""
Provides interface n2v interface to Psi4
"""
from .engine import Engine
import numpy as np
from opt_einsum import contract
try:
import psi4
psi4.set_options({"save_jk" : True})
has_psi4 = True
except ImportError:
has_psi4 = False
if has_psi4:
from ..grid import Psi4Grider
class Psi4Engine(Engine):
"""
Psi4 Engine Class
"""
def set_system(self, molecule, basis, ref='1', pbs='same', wfn=None):
"""
Initializes geometry and basis infromation
Parameters
----------
molecule: psi4.core.Molecule
Molecule of the system used
basis: str
Basis set of calculation
ref: int
Reference: Restricted -> 1
Unrestricted -> 2
pbs: str
Basis set of potential used
wfn : psi4.core.{RHF, UHF, RKS, UKS, Wavefunction, CCWavefuncion...}
Psi4 wavefunction object
"""
self.mol = molecule
#Assert units are in bohr
# units = self.mol.to_schema(dtype='psi4')['units']
# if units != "Bohr":
# raise ValueError("Units need to be set in Bohr")
self.basis_str = basis
self.ref = ref
self.pbs = pbs
self.pbs_str = basis if pbs == 'same' else pbs
self.nalpha = wfn.nalpha()
self.nbeta = wfn.nbeta()
self.wfn = wfn
def initialize(self):
"""
Initializes basic objects required for the Psi4Engine
"""
self.basis = psi4.core.BasisSet.build( self.mol, key='BASIS', target=self.basis_str)
self.pbs = psi4.core.BasisSet.build( self.mol, key='BASIS', target=self.pbs_str)
self.nbf = self.basis.nbf()
self.npbs = self.pbs.nbf()
self.mints = psi4.core.MintsHelper( self.basis )
self.jk = self.generate_jk()
self.grid = Psi4Grider(self.mol, self.basis, self.ref)
def get_T(self):
"""Kinetic Potential in ao basis"""
return np.array( self.mints.ao_kinetic() )
def get_Tpbas(self):
"""Kinetic Potential in pbs"""
return np.array( self.mints.ao_kinetic(self.pbs, self.pbs) )
def get_V(self):
"""External potential in ao basis"""
return np.array( self.mints.ao_potential() )
def get_A(self):
"""Inverse squared root of S matrix"""
A = self.mints.ao_overlap()
A.power( -0.5, 1e-16 )
return np.array( A )
def get_S(self):
"""Overlap matrix in AO basis"""
return np.array( self.mints.ao_overlap() )
def get_S3(self):
"""3 Orbitals Overlap matrix in AO basis"""
return np.array( self.mints.ao_3coverlap(self.basis,self.basis,self.pbs) )
def get_S4(self):
"""
Calculates four overlap integral with Density Fitting method.
S4_{ijkl} = \int dr \phi_i(r)*\phi_j(r)*\phi_k(r)*\phi_l(r)
Parameters
----------
wfn: psi4.core.Wavefunction
Wavefunction object of moleculep
Return
------
S4
"""
print(f"4-AO-Overlap tensor will take about {self.nbf **4 / 8 * 1e-9:f} GB.")
aux_basis = psi4.core.BasisSet.build(self.mol, "DF_BASIS_SCF", "", "JKFIT", self.basis_str)
S_Pmn = np.squeeze(self.mints.ao_3coverlap(aux_basis, self.basis, self.basis ))
S_PQ = np.array(self.mints.ao_overlap(aux_basis, aux_basis))
S_PQinv = np.linalg.pinv(S_PQ, rcond=1e-9)
S4 = contract('Pmn,PQ,Qrs->mnrs', S_Pmn, S_PQinv, S_Pmn)
return S4
def generate_jk(self, gen_K=False):
"""
Creates jk object for generation of Coulomb and Exchange matrices
1.0e9 B -> 1.0 GB
"""
jk = psi4.core.JK.build(self.basis)
memory = int(jk.memory_estimate() * 1.1)
jk.set_memory(int(memory))
# added by Ehsan
# .set_do_K(gen_K = False) determines if exchane matrices should be calculated or not
jk.set_do_K(gen_K)
jk.initialize()
#print("jk: ", jk)
return jk
def compute_hartree(self, Cocc_a, Cocc_b):
"""
Generates Coulomb and Exchange matrices from occupied orbitals
"""
Cocc_a = psi4.core.Matrix.from_array(Cocc_a)
Cocc_b = psi4.core.Matrix.from_array(Cocc_b)
self.jk.C_left_add(Cocc_a)
self.jk.C_left_add(Cocc_b)
self.jk.compute()
self.jk.C_clear()
J = (np.array(self.jk.J()[0]), np.array(self.jk.J()[1]))
return J
def hartree_NO(self, Dta):
"""
Computes Hartree potential in AO basis from Natural Orbitals
"""
if self.wfn is None:
raise ValueError('Please provide a wfn object to the Inverter, i.e., Inverter.eng = wfn')
if type(self.wfn) == psi4.core.CCWavefunction:
C_NO = psi4.core.Matrix(self.nbf, self.nbf)
eigs_NO = psi4.core.Vector(self.nbf)
self.wfn.Da().diagonalize( C_NO, eigs_NO, psi4.core.DiagonalizeOrder.Descending )
occ = np.sqrt( np.array(eigs_NO) )
new_CA = occ * np.array(C_NO)
assert np.allclose( new_CA @ new_CA.T, Dta )
if self.ref == 1:
new_CB = np.copy( new_CA )
else:
self.wfn.Db().diagonalize( C_NO, eigs_NO, psi4.core.DiagonalizeOrder.Descending )
occ_b = np.sqrt( np.array( eigs_NO ) )
new_CB = occ_b * np.array( C_NO )
J0 = self.compute_hartree(new_CA, new_CB)
return J0
def run_single_point(self, mol, basis, method):
"""
Run a standard energy calculation
"""
wfn_temp = psi4.energy(init+"/" + self.basis_str,
molecule=self.mol,
return_wfn=True)[1]
if self.ref == 1:
D = np.array(wfn_temp.Da()) + np.array(wfn_temp.Db())
C = np.array(wfn_temp.Ca())
e = np.array(wfn_temp.epsilon_a())
else:
D = np.stack( (np.array(wfn_temp.Da()), np.array(wfn_temp.Db())) )
C = np.stack( (np.array(wfn_temp.Ca()), np.array(wfn_temp.Cb())) )
e = np.stack( (np.array(wfn_temp.epsilon_a()), np.array(wfn_temp.epsilon_b())) )
return D, C, e