Knowledge Bank

The absorption spectrum of dichloroborane $BHCl2$ was accidentally recorded during Fourier transform emission measurements of HBO. Gaseous dichloroborane was generated by the reaction of amorphous boron powder with $CaCl2$ at 1400 C. The bands centred near 2617, 1089 and $892cm-1$ were assigned as the $\nu 1$ (B-H stretch), the $\nu 5$ (HBCl bend), and the $\nu 6(BCl2$ antisymmetric stretch) fundamental modes, respectively. Modular constants were determined from rotational analyses of these bands. This is a first analysis of the rotational structure of the $\nu 5$ and $\nu 6$ modes.