quantumlib / OpenFermion-PySCF

OpenFermion plugin to interface with the electronic structure package PySCF.
Apache License 2.0
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Implementation of Hamiltonian using natural orbitals #67

Open NoniaVS opened 1 year ago

NoniaVS commented 1 year ago

Dear developers,

I implemented some additions to the code that I think could be useful. I added the option to construct the Hamiltonian using the natural orbitals obtained from an unrestricted Hartree-Fock calculation. In this implementation I replace the canonical orbitals by the natural orbitals if this option is requested. I have also included the option to use a HOMO-LUMO mixed guess for the UHF as written in the PYSCF example 56 (https://github.com/pyscf/pyscf.github.io/blob/master/examples/scf/56-h2_symm_breaking.py).

Feel free to do the modifications to the code that you consider.