Chapter 11, Problem 11D.5BE

Interpretation Introduction

Interpretation:

Whether the out of plane mode of planar ${\text{AB}}_{\text{3}}$ molecule is infrared or Raman active has to be predicted.

Concept introduction:

The complex vibrations exhibit by the polyatomic molecule is known as normal modes of vibrations.  The total number of vibrational degrees of freedom for nonlinear molecule is represented by $3N-6$.  The total number of vibrational degrees of freedom for linear molecule is represented by $3N-5$.