Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523, Université de Lille 1, F-59655 Villeneuve d'Ascq, France.
J Phys Chem A. 2012 Feb 16;116(6):1565-70. doi: 10.1021/jp211611t. Epub 2012 Feb 6.
The microwave spectrum of cyclopropylphosphine-borane, C(3)H(5)PH(2)-BH(3), has been investigated in the frequency range 150-195 GHz. The spectral assignment was supported by high level ab initio calculations. Two stable conformations have been predicted: the most stable antiperiplanar form and synclinal form that is higher in energy by 7.3 kJ/mol. In the observed spectra, only the most stable antiperiplanar (ap) form has been assigned. The analysis of the rotational spectra in the lowest excited vibrational states of the ap conformer has enabled determination of the potential function for the C-P torsional mode in the vicinity of equilibrium position. The barrier to internal rotation of the BH(3) top has been determined to be 9.616(15) kJ/mol and agrees well with quantum chemical calculations.
环丙基膦-硼烷（C(3)H(5)PH(2)-BH(3)）的微波光谱在 150-195GHz 的频率范围内进行了研究。通过高精度的从头算计算支持了光谱的归属。预测了两种稳定的构象：最稳定的反式构象和能量高 7.3kJ/mol 的顺式构象。在观察到的光谱中，只分配了最稳定的反式构象。对反式构象最低激发振动态的转动光谱的分析，使得能够确定在平衡位置附近的 C-P 扭转模式的势能函数。BH(3)顶端的内旋转势垒被确定为 9.616(15)kJ/mol，与量子化学计算吻合得很好。
