next up previous contents
Next: Asymmetric Stretching Mode Up: Spectroscopic Properties of Carbon Previous: Symmetric Stretching Mode:   Contents

Bending Mode

The bending motion of the carbon dioxide molecule has associated dipole fluctuations as shown in figure.

Figure: The bending motion of the carbon dioxide molecule showing fluctuation in the dipole moment
\begin{figure}\centerline{\hbox{\psfig{file=bend.ps,height=0.25\textheight}}}\end{figure}

The vibration is 'infrared active' since there is a periodic alteration of the dipole moment. The bending mode involves two separate modes of vibrations each moving in orthogonal direction with respect to the other and is degenerate since both modes have same energy. The frequency of the mode is

$\displaystyle \nu_2$ $\displaystyle =$ $\displaystyle 2.00\times 10^{13} s^{-1}$  
  $\displaystyle =$ $\displaystyle 667 /cm$  

The associated quantum number is denoted by $ v_2$.


Ms Rajwinder Kaur 2004-11-11