Chapter 11, Problem 11A.2DQ

Interpretation Introduction

Interpretation:

The physical origin of line widths in absorption and emission spectra has to be stated.  Whether the contribution of species in condensed phase and in gas phase is same or not has to be stated.

Concept introduction:

The gross selection rule for pure rotational transition is that the molecule must possess a permanent electric dipole moment.  The molecules possessing dipole moment is considered as a handle that stirs the electromagnetic field into oscillation.  Polar molecules possess electric dipole moment and thus are classified as microwave active.