Philicity indices within the spin-polarized density-functional theory framework.

The electrophilicity index is analyzed within the framework of spin-polarized density-functional theory. In this context, constrained philicities, ω_N≡(μ_N)²/(2η_NN), are introduced in order to define the capability of a system to acquire or donate electrons in a process at constant spin number. The spin-philicity/spin-donicity indices, ω_S^±≡(μ_S^±)²/(2η_SS), are examined and rationalized here as the philicity of a given system to change its spin-polarization state, as being defined through the spin potential μ_S and spin hardness η_SS for a process at constant number of electrons. The local extension of these indices has been also outlined and numerical results have been discussed on the analysis of the electrophilic nature of some simple carbene systems both in the singlet and triplet states. [ABSTRACT FROM AUTHOR]