The Hartree Fock method is used in Quantum Chemistry to approximate the interactions between different particles enabling the recent use of Quantum computers to produce or calculate properties of new molecules.
Now particles is a very generic term that means that the HF method can be used to understand how atoms combine to form molecules , how molecules or atoms form the composite structures etc.
The section of chemistry dealing with these kind of interactions is called Electronic Structure Theory.
If one want to understand the HF method Have to keep in mind the following things
1. HF Method does not have an analytical solution only a numerical solution is possible.
That means involves a lot of number crunching which classical computers cannot afford as number of interacting particles
increases. So a quantum computer becomes the right choice.
2.Perturbation theory is used to make moledule finding using HF method more accurate.
There is interaction between electrons and the field changes of an electron can have effect on other atoms.
Perturbation theory is a branch of mathematics which try to model weak disturbances to a stable system.
So calculations involving HF method will have a stable term and a term due to the perrubation caused by the other electrons.
Understanding HF method and Perturbation theory will help to work with the Qiskit to search for new molecules.