Potential Function for the Ring Puckering Vibration of B2H6 and B2D6

Abstract

The v = 1 → 2 transition of the ring puckering mode of B2H6 has been observed at 389.5±0.5 cm−1 and identified on the basis of relative intensity measurements of the rotational fine structure of the overlapped v = 0 → 1 and v = 1 → 2 bands. The band center for the ring puckering fundamental has been determined to be 369.3 cm−1 utilizing an asymmetric rotor calculation. The potential function for the ring puckering vibration based on the v = 0 → 1 and v = 1 → 2 transitions is V(X) = 25.25(X4+11.78X2), where X is a reduced coordinate. The band centers for the v = 0 → 1 and v = 1 → 2 bands for B2D6 were assigned to the ``holes'' in the band envelope at 261.3 and 272.6 cm−1, respectively. The rotational fine structure in the bands of the deuterated molecule was not resolved. The potential for the deuterated molecule predicted from a reduced mass model is V(X) = 15.93(X4+14.71X2).