The infrared spectrum, equilibrium structure and harmonic and anharmonic force field of thioborine, HBS

Infrared spectra of the two stretching fundamentals of both HBS and DBS have been observed, using a continuous flow system through a multiple reflection long path cell at a pressure around 1 Torr and a Nicolet Fourier Transform spectrometer with a resolution of about 0·1 cm-1. The v 3 BS stretching fundamental of DBS, near 1140 cm-1, is observed in strong Fermi resonance with the overtone of the bend 2v 2. The bending fundamental v 2 has not been observed and must be a very weak band. The analysis of the results in conjunction with earlier work gives the equilibrium structure (r e(BH) = 1·1698(12) Å, r e(BS) = 1·5978(3) Å) and the harmonic and anharmonic force field.