Chapter 11, Problem 11C.8E

Interpretation Introduction

Interpretation:

Wavenumber of the line originating from the rotational state of ${}^1{\text{H}}^{81}Br$ with $J=\text{ 2}$ has to be determined where $\overline{\text{B}}\text{= 8}{\text{.360 cm}}^{-1}$.

Concept Introduction:

In the vibrational transitions of gas molecules are accompanied by rotational transitions. Due to this the spectrum is split into three branches namely, Q branch $\left(\Delta J\text{ = 0}\right)$, P branch $\left(\Delta J\text{ = }-\text{1}\right)$ and R branch $\left(\Delta J\text{ = +1}\right)$.

Wavenumber originated for the absorption line in the R branch is given,

  ${\overline{\nu }}_J=\overline{\nu }\text{ + 2}\overline{\text{B}}\left(J+1\right)$