CCL:G: TDDFT in gaussian

[Jens Spanget-Larsen <spanget!A!ruc.dk>]

 Sent to CCL by: Jens Spanget-Larsen [spanget^^ruc.dk]
 Dear Agalya Govindasamy,
maybe you already solved your problem. But nevertheless, for a closed
 shell species, it is easy to calculate the percentage contributions
 from
 the coefficients printed by a Gaussian TDDFT run. The coefficients
 refer
 to micro-configurations (not spin adapted). If you want the percentage
 contribution from the pertinent singlet configuration, you must square
 the printed coefficient and multiply it by 2 x 100. For instance, the
 contribution from the 129 -> 138 excitation in the first of your
 examples amounts to
 0.45069^2 x 2 x 100 = 40.62%.
 In your second example, you get for the 130 -> 132 excitation
 0.67417^2 x 2 x 100 = 90.90%.
Please note that Gaussian by default prints only contributions larger
 than a certain treshold. There is an IOP input parameter that leads to
 printing also of smaller contributions, but I do not have it at hand.
 Good Luck!
 Jens >--<
   ------------------------------------------------------
   JENS SPANGET-LARSEN         Office:      +45 4674 2710
   Department of Chemistry     Fax:         +45 4674 3011
   Roskilde University (RUC)   Mobile:      +45 2320 6246
   P.O.Box 260                 E-Mail:     spanget-#-ruc.dk
   DK-4000 Roskilde, Denmark   http://www.ruc.dk/~spanget
   ------------------------------------------------------
 Agalya Govindasamy agalya81{}gmail.com wrote:
>  Sent to CCL by: "Agalya  Govindasamy" [agalya81-x-gmail.com]
>  Dear CCL users,
>  I would like to know about calculating the precentage contribution of excitation
>  coefficients given in the TDDFT output.
>  For example, the following excitation shows mixture of transitions with
>  different excitation coefficients.
>  Excited State  31:	Singlet-A	3.6351 eV	341.07 nm	f=0.0001
>  119 ->132	0.11466
>  124 ->138	0.16417
>  124 ->140	-0.16712
>  129 ->138	0.45069
>  129 ->140	-0.3978
>  129 ->141	-0.12337
>  130 ->136	-0.10225
> I have seen in some journals, that they have mentioned the
>  coefficients as percentage. Here since there are many transitions, could anyone
>  can please tell me how to calculate the percentage of the coefficients.
>  
>  This may be a stupid question.
>  
>  Does everyone divide the particular coefficient divided by the sum of
>  all the coefficients and then multiplied by 100 to get the percentage value?
>  
>  If that is correct, then how to get percentage value of the coefficient for
>  excitations like the following case
>  Excited State   1:	Singlet-A	1.5328 eV	808.90 nm	f=0.0287
>  130 ->132	0.67417
> can i mention it as 100%.
>  
>  Thankyou in adavnce