Structure and energy studies of β-diketonates.: X.: Molecular structure of Sc(aa)3 according to gas-phase electron diffraction data

Synchronous electron diffraction and mass spectrometric investigation of the saturated vapor of scandium tris-acetylacetonate was carried out. It was stated that at 155(5)degreesC the vapor contains only monomeric Sc(aa)(3) molecules, whose structural parameters r(a), r(g), and r(alpha) were determined. The internuclear distances in the chelate ring were found to be r(alpha)(Sc-O) = 2.076(4), r(alpha)(O-C) = 1.271(3), r(alpha)(C-C-r) = 1.386(4) Angstrom. The coordination polyhedron ScO6 has a nearly antiprism structure of D-3 symmetry. The angle of rotation of the O-O-O trigonal faces relative to their position in a regular prism is 20.8(1.1)degrees.