Vibrations cause changes in a molecules conformation and are

Vibrations cause changes in a molecule\'s conformation and are the basic \"unit\" of structural change. In other words, all conformational changes can be thought of as resulting from a series of vibrations. As one example, rotation from an eclipsed to staggered geometry is simply a consequence of one or several vibrations that happen in quick succession. On page 221, it was said that the time period of a molecular vibration is around 1 picosecond (10-12 s) while the lifetime of a rotational isomer is around 100 picoseconds. Based on these numbers, what is the probability that a vibration leads to bond rotation? (Recall that the time period for an event is just the inverse of the event\'s frequency: t = 1 / f). A. 1 B. 0.1 C. 0.01 D. 0.00001

Solution

For 1vibration time is 1pico sec.and for 1 rotation time is 100 pico sec. So the probability for one vibration leads to a rotaion will be 1/100= .01

Hence the answer is C) 0.01