qrunch.chemistry.ground_state_problem.calculators.tools.initial_ansatz.electron_pair_hartree_fock
Module designed to generate an initial state circuit that corresponds to a paired Hartree-Fock wave function.
The paired-electron approximation is used, meaning that electrons are assumed to be paired in spatial orbitals.
The Hartree-Fock wave function is an approximation that assumes that the wave function of the electronic system can be taken as s single Slater determinant, or a single spin-adapted configuration state function (CSF) which is a linear combination of Slater determinants that are eigenfunctions of the :math:S^{2} operator. However, in this implementation we do not implement the CSF.
The resulting quantum circuit will have a number of qubits equal to the number of spatial orbitals.
Classes
Class to generate and store information about an electron pair Hartree-Fock state. |
- class ElectronPairHartreeFockAnsatz
Bases:
InitialAnsatzClass to generate and store information about an electron pair Hartree-Fock state.
This state is intended to be used as an initial state for quantum chemistry calculations with quantum computers. Generally, this state will correspond to a classical bitstring (1,…,1 ,0,…,0) where the total number of qubits is the number of spatial orbitals. Each spatial orbital can be populated by an electron pair.
- __init__(molecular_electron_pair_configuration: MolecularElectronPairConfiguration) None
Initialize a ElectronPairHartreeFockAnsatz.
- Parameters:
molecular_electron_pair_configuration (MolecularElectronPairConfiguration) – Electron pair configuration to use.
- Return type:
None