Ldwdin population analysis

Ldwdin population analysis avoids the problem of negative populations or populations greater than 2. Some quantum chemists prefer the Ldwdin approach to that of Mulliken as the charges are often closer to chemically intuitive values and are less sensitive to basis set. 

Hartree-Fock and Kohn-Sham theories, and for performing the Ldwdin population analysis (Section 9.1). 

In the Lowdin approach to population analysis [Ldwdin 1970 Cusachs and Politzer 1968] the atomic orbitals are transformed to an orthogonal set, along with the molecular orbital coefficients. The transformed orbitals in the orthogonal set are given by ... 

The Mulliken and Lowdin methods are just particular examples of a whole family of population analysis using S" D S " matrices. The Mulliken and Ldwdin methods... 

This is precisely the leading idea of Lowdin population analysis. It can be observed that the mathematical use of the trace of P S, i.e., Tr(P S) = Tr(P S -"S") = Tr(S"P S -"), yields an infinite number of possibilities, among which the approaches of Mulliken and Ldwdin are particular cases. In... 

Originally devised by Ldwdin, albeit from a slightly different perspective, the concept of natural orbitals has been extended by Reed and Weinhold and constitutes the basis of the natural population analysis (NPA). This method attempts... 

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