DUGi

Local spins: improved Hilbert-space analysis

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@294983

The decomposition of h <(S) over cap (2)> for a general wave function has been carried out in the framework of the Hilbert-space analysis. The one and two-center components fulfill all physical requirements imposed to date. An inherent ambiguity of the Hilbert-space decomposition of a two-electron quantity, in particular using a Mulliken-type scheme, is also discussed in detail. The formalism of effective atomic densities has allowed us to derive in a simple manner appropriate expressions for the decomposition of <(S) over cap (2)> i in the framework of Hilbert space analysis that are consistent with Mulliken population analysis and related quantities. Using a particular mapping we have derived the Hilbert-space expressions also in the framework of Lowdin population analysis in a straightforward manner. The numerical results obtained with the latter formalism have proved to be more robust and reliable

Financial help has been furnished by the Spanish MICINN Projects No. CTQ2011-23441/BQU, CTQ2011-23156/BQU and Accion Complementaria del MCI (PCI2006-A7-0631). Financial support from MICINN and the FEDER fund (European Fund for Regional Development) was also provided by grant UNGI08-4E-003. E. R.-C. acknowledges support from the Spanish FPU program (Grant No. AP2008-01231). E. M. acknowledges financial support from the EU under a Marie Curie Career Integration grant (PCI09-GA-2011-294240) and the Beatriu de Pinos program from AGAUR for the postdoctoral grant (BP_B_00236). I. M. acknowledges partial financial support from the Hungarian Scientific Research Fund (grant OTKA 71816)

Royal Society of Chemistry