The Electron Density Distribution in Crystals of η ⁶ –[1,4–dihydrospiro(2 H –3,1–benzoxazine–2,1′–cyclohexane)]tricarbonylchromium(0): Experiment vs Molecular Invariom

In this paper we present the results of a high–resolution single crystal X–ray diffraction experiment of η⁶–[1,4–dihydrospiro(2H–3,1–benzoxazine–2,1′–cyclohexane)]tricarbonylchromium(0) and a subsequent charge density study based on a topological analysis according to quantum theory of atoms in molecules. The key point of this investigation is a comparison of the experimental topological characteristics of the electron density in the chromium atom coordination sphere with the experimentally–theoretical ones obtained on the basis of “whole–molecule” aspherical scattering factors (molecular invariom). We have shown that molecular invarioms adequately reproduce the deformation electron density in the coordination sphere of the chromium atom, molecular graphs, noncovalent interaction (NCI) index isorsurfaces as well as the population of d–orbitals of the Cr atom. In addition, we found that a comparative analysis of atomic charges and volumes obtained experimentally and experimentally–theoretically allows “to find” a reasonable value of the atomic charge.