Topology of the electron localization function
in complex xenon fluorides

Noble gas complex fluorides exhibit many interesting structural features,
which worthies a detail study. We report the results of the quantum chemical
calculations of complex xenon fluorides, XeF_{5}AF_{6} (A = As,
Sb, Bi, V, Nb, Ta).
Software package AIMPAC was modified to provide a calculation of the electron
localization function (ELF) and topological analysis of this function. All the
bond critical points in the electron density of these compounds possess a
positive value of Laplacian of the electron density: that is typical for
closed-shell atomic interactions. It was found that ELF of molecules
XeF_{5}^{+}VF_{6}^{-}, XeF_{5}^{+}NbF_{6}^{-} and XeF_{5}^{+}TaF_{6}^{-} exhibits 13 core attractors, i.e. C(A),
C(Xe) and C(F1-11), 5 valence disynaptic attractors V(Fi,Xe) sited on Fi-Xe
bonds (i = 1-5) and valence monosynaptic attractors V(F1-5), two per each F
atoms. The later attactors provide a week bond between F and Xe atoms of
adjacent molecules an explain the spatial organization the molecular ensembles
and clusters in solids. It was demonstrated that the ELF value of disynaptic
attractors V(Xe,F_{6}) increased in series V-Nb-Ta and As-Sb-Bi
together with the bond distances. Simultaneously, the bond strength and
reactivity of substances decrease.