STRUCTURE OF TRIS(1,1,1,5,5,5-HEXAFLUORO-2,4-PENTANEDIONATO)ALUMINUM(III) DETERMINED BY GAS-PHASE ELECTRON-DIFFRACTION

The rg structure of tris(1,1,1,5,5,5-hexafluoroacetylacetonato)aluminum(III) has been determined by gas phase electron diffraction. The experimental data were found to be consistent with a D3 model in which the oxygen atoms of the three ligands are arranged in a slightly distorted octahedron about the aluminum atom [∠ OAlO for the ligand is 87.2° (1.4)]. The aluminumoxygen bond length obtained [AlO = 1.893(14) Å] is in excellent agreement with the value previously obtained by X-ray diffraction for the related acetyl-acetonato complex of aluminum [AlO = 1.893(14) Å]. Structural parameters for the ligand [CO = 1.277(11) Å, CCring = 1.412(14) Å, CCF3 = 1.561(11) Å, and CF = 1.338(3) Å] are in excellent agreement with the values obtained in an earlier electron diffraction study of the Cr(III) complex with hexafluoroacetylacetonate. The resulting structure was found to agree quite well with the predictions based on a force law model for tris bidentate complexes developed by Kepert. © 1979.