Abstract The sum and difference bands of cyclopropylsilane-d 3 in the 1400–1700 cm− 1 region arising from combinations of the internal rotation with the Si D stretching mode have been recorded and analyzed. The data correspond to a barrier to internal rotation of 651 cm− 1, somewhat less than the value of 694 cm− 1 determined for the undeuterated species. Similarly, the combination band spectra of cyclopropylgermane in the 1950–2200 cm− 1 ...
