Dear Iresh,

Using the TDDFT method installed in G09 you can get the excitation coefficient for each of the excitation in the molecule. For closed shell systems, the square of this coefficient times 100 gives the percentage contribution of that excitation. Thus the larger the coefficient is the higher is the excitation contribution.

Please note, that for open shell systems the calculation for the excitation contribution is different from those of the closed shell systems.

Hoping this will be helpful,

Rafik

Thanks again Rafik Karaman, I really appreciate your help.

 I am using GAMESS  for all those calculations .

Is the excitation amplitude the same to excitation coefficient in TDDFT?