title: Ab initio molecular orbital study on the Ge-, Sn-, Zr- and Si/Ge-mixed silsesquioxanes.
abstract: For the purpose of designing new functional silsesquioxanes (POSS), the structure and stability of the analogous compounds of the heavier group 14 and 4 elements such as germanium (Ge-POSS), tin (Sn-POSS) and zirconium (Zr-POSS) analogues of POSS were investigated and compared with those of the parent POSS and the titanium analogue (Ti-POSS) with electronic structure theory calculations, including electron correlation effects. In order to obtain information about the metalloxane (-X-O-X-) linkage, the structures and properties of the building blocks of metallasilsesquioxanes, such as dimetalloxanes, H(OH)2XOX(OH)2H, X = Ge, Sn and Zr, and cyclometalloxanes, [H(OH)XO]n , n = 3-6, X = Ge, Sn and Zr, were examined. The stability of the Si/Ge-mixed POSS were also studied in comparison with POSS and the completely germanium-substituted POSS.
authors.affiliation: Department of Chemistry and Chemical Biology, Graduate School of Engineering, Gunma University, Kiryu 376-8515, Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Kudo
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Akasaka
authors.forename: Mark S
authors.initials: MS
authors.lastname: Gordon