Directivity of the Intramolecular O→Si Bond in Pentacoordinate Organosilicone Compounds

According to the data of X-ray diffraction analysis and quantum chemical calculations, in the hypervalent silicon compounds where the coordination cycle is closed by the C=O-->Si-F fragment, the O-->Si interatomic distance is governed by the orientation of the silicon atom determined by the C=O-->Si angle. This is an indication of a directivity of the coordination bond O-->Si; a regular variation in the nature of the latter is reflected in the observed dependence of the O-->Si distance on the C=O-->Si angle.