Artículo de revista
How to Compute the Fukui Matrix and Function for Systems with (Quasi-)Degenerate States
Fecha
2014Registro en:
J. Chem. Theory Comput. 2014, 10, 202−210
DOI: 10.1021/ct400874d
Autor
Bultinck, Patrick
Cárdenas Valencia, Carlos
Fuentealba Rosas, Patricio
Johnson, Paul A.
Ayers, Paul W.
Institución
Resumen
A system in a spatially (quasi-)degenerate
ground state responds in a qualitatively different way to a
change in the external potential. Consequently, the usual
method for computing the Fukui function, namely, taking the
difference between the electron densities of the N- and N ± 1
electron systems, cannot be applied directly. It is shown how the
Fukui matrix, and thus also the Fukui function, depends on the
nature of the perturbation. One thus needs to use degenerate
perturbation theory for the given perturbing potential to
generate the density matrix whose change with respect to a
change in the number of electrons equals the Fukui matrix.
Accounting for the degeneracy in the case of nitrous oxide
reveals that an average over the degenerate states differs
significantly from using the proper density matrix. We further
show the differences in Fukui functions depending on whether a Dirac delta perturbation is used or an interaction with a true
point charge (leading to the Fukui potential).