A simple approximation beyond Hartree - Fock
نویسندگان
چکیده
The form of a real AT-body fermion wave function when expanded in Slater determinants of natural orbitals is investigated using a computer. I t is found that in the case when the number of natural orbitals is N f 2 there is a considerable reduction in the number of Slater determinants required. This offers the possibility of calculating atomic wave functions which are significantly more accurate than Hartree-Fock without an excessive amount of additional computing. In this approximation, pairing of orbitals occurs without invoking the concept of spin.
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