Is Hartree-Fock more accurate than DFT?

Instead of focusing on wave functions and orbitals, DFT focuses on the electron density (although it usually employs orbitals to get the density). It includes an approximate treatment of electron correlation and therefore should be more accurate than Hartree-Fock theory.

What does Hartree-Fock do?

In computational physics and chemistry, the Hartree–Fock (HF) method is a method of approximation for the determination of the wave function and the energy of a quantum many-body system in a stationary state.

What is Hartree-Fock exchange?

The exchange term results from our inclusion of the Pauli principle and the assumed determinantal form of the wavefunction. The effect of exchange is for electrons of like-spin to avoid each other. Hartree-Fock theory, by assuming a single-determinant form for the wavefunction, neglects correlation between electrons.

What is a basis set in computational chemistry?

A basis set in theoretical and computational chemistry is a set of functions (called basis functions) which are combined in linear combinations (generally as part of a quantum chemical calculation) to create molecular orbitals.

What are the variational parameters used in the Hartree-Fock method?

The variational parameters of the method are the single-particle wave functions composing the many-body wave function. We will focus the present article on the Hartree-Fock method for fermionic systems.

What is the purpose of the Slater determinant?

In quantum mechanics, a Slater determinant is an expression that describes the wave function of a multi-fermionic system. It satisfies anti-symmetry requirements, and consequently the Pauli principle, by changing sign upon exchange of two electrons (or other fermions).

What are Slater Condon parameters?

The Slater —Condon parameters F°(3s, 3s), F°(3s,3p), and F°{3p,3p) were calculated using the Anno electron transfer equations A+ + A+ -> A + A2 + . The obtained semi- empirical values of the Slater —Condon parameters are suitable for the use in semiempirical methods of calculation of electronic structure of molecules.