title: The gas-phase structure of 1-selena-closo-dodecaborane(11), 1-SeB11H11, determined by the concerted use of electron diffraction and computational methods.
abstract: The molecular structure of 1-selena-closo-dodecaborane(11), 1-SeB11H11, has been determined by the concerted use of quantum chemical calculations and gas-phase electron diffraction. The structure has C(5v) symmetry and is distorted from a regular icosahedron mainly through the expansion of the pentagon of boron atoms adjacent to selenium, with r(a3,1)(B-B) = 192.2(2) pm. The Se-B bond length is extremely well determined [r(a3,1) (Se-B) = 212.9(2) pm] and this is reflected by a pronounced peak in the radial-distribution curve. The accuracy of the experimental structure, as well as that calculated at the MP2/962(d) level, has been gauged by comparison of the 11B chemical shifts (calculated at two different gauge-including atomic orbitals (GIAO) levels) with experimental NMR values. The inclusion of electron correlation in the magnetic property calculations (GIAO-MP2) gave superior results to those carried out using GIAO-Hartree-Fock.
authors.affiliation: Institute of Inorganic Chemistry, Academy of Sciences of the Czech Republic, CZ-25068, Rez near Prague, Czech Republic. hnyk@iic.cas.cz
authors.forename: Drahomír
authors.initials: D
authors.lastname: Hnyk
authors.forename: Derek A
authors.initials: DA
authors.lastname: Wann
authors.forename: Josef
authors.initials: J
authors.lastname: Holub
authors.forename: Michael
authors.initials: M
authors.lastname: Bühl
authors.forename: Heather E
authors.initials: HE
authors.lastname: Robertson
authors.forename: David W H
authors.initials: DW
authors.lastname: Rankin