Conventional wave function-based quantum theory

It is instructive to compare the Hohenberg-Kohn theorems to their counterparts in conventional wave function-based quantum theory. The wave function provides a... 

The FC method is completely different from the conventional quanmm chemistry. In the state-of-the-art quantum chemistry, one first defines Harfree-Fock orbitals based on the initially chosen basis set and then expands many-electron correlated wave functions by means of the Hartree-Fock orbitals. In this approach, any theory lies between the Hartree-Fock and the full Cl and so, tiie full Cl is a goal of this type of the theory. However, the full Cl cannof be tiie exacf solution of the Schrodinger equation because of the incompleteness of the basis set first introduced. When we use numerical Hartree-Fock that is free from the basis set, the full Cl becomes infinite expansion that cannot be handled in principle. 

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