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Siddheshwar Chopra

Dear Sir,
I am for the first time going to try UV-Visible spectra. Could you tell me what kind of spectra does it calculate?? Is it Absorption or Emission UV-Vis spectra??
In both the cases, how do I specify the range of wavelengths on x-axis in i/p file? And also what are the y-axis data? Are they the absorption Intensities/ emission Int. or something else?
Could you provide me a sample i/p file for say Benzene with all the above data?


On Mon Apr 22 '13 2:55pm, Thomas wrote
>Dear Siddheshwar,

>Yes, there is. RAMAN spectra can be obtained with RUNTYP=RAMAN, though you will need to do a few calculations prior to this:

>- First, you need to do a geometry optimization.
>- Secondly, you need to do a Hessian calculation on the optimized geometry (RUNTYP=HESSIAN). Note that it is possible to do this in the same run as the geometry optimization by specifying $STATPT HSSEND=.T. $END
>- Finally, you can run a RUNTYP=RAMAN job. You should specify $FORCE RDHESS=.T. $END and provide the complete $HESS group, that you obtained in the previous step, in your input.

>As for UV/vis spectra, these can be calculated with TDHF, TDDFT, CIS, and (X)MCQDPT2. The first three methods print out oscillator strengths. (X)MCQDPT2 on the other hand prints out transition dipole moments which you will have to convert to oscillator strengths yourself.
>Kind regards,
>On Sun Apr 21 '13 9:56pm, Siddheshwar Chopra wrote
>>Dear sir,
>>Do we have an option in firefly8 tp get uv visible and raman spectrum??

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