The structure of 1-thia-closo-decaborane(9), 1-SB(9)H(9), as determined by microwave spectroscopy and quantum chemical calculations.
The microwave spectrum of 1-thia-closo-decaborane(9), 1-SB(9)H(9), has been investigated in the 12-61 GHz spectral region. The molecule has C(4v) symmetry. The spectra of five isotopomers have been assigned, and a precise substitution structure of the non-hydrogen atoms has been determined. It was found that the axial sulfur atom causes a substantial expansion of the B(4) belt adjacent to sulfur and hence leads to a significant distortion from a regular bicapped square antiprismatic structure. The experimental work has been supplemented by high-level ab initio (MP2/6-311G**) and density functional theory calculations (B3LYP/6-311G** and B3LYP/cc-pVTZ). The agreement between the substitution structure and the two DFT calculations is very good in each case. The agreement is considerably poorer for the MP2/6-311G** calculations, particularly for the sulfur-boron bond length.
Møllendal
Harald
H
Department of Chemistry, University of Oslo, Sem Saelands vei 26, P.O. Box 1033, NO-0315 Oslo, Norway. harald.mollendal@kjemi.uio.no
Samdal
Svein
S
Holub
Josef
J
Hnyk
Drahomír
D