THE MICROWAVE SPECTRUM OF HEXABORANE

Abstract

The MW-spectrum of $B_{6}H_{10}$ has been assigned. The rotational constants are $A = 5136.4 ~MHz, B = 4987.3 ~MHz, C = 3077.8 MHz$. Previously taken NMR spectra at different temperatures show a change of molecular symmetry from $C_{s} to C_{5v}$. The heavy atom MW substitution structure shows a pentagonal pyramidal structure of $C_{s}$ symmetry which is close to a symmetric top. Effects of the motion of the 4 bridging protons changing positions among the 5 possible basal sites of the pyramid are being investigated.