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Re^5: Help needed with the Transition density matrix determination and analysis....

Siddheshwar Chopra

Dear Pavlo Sir and Alex Sir,
Thank you so much for the useful information. Alex sir I am really happy to know that it is possible to find TDM from PUNCH file (from TDDFT calc.). I would request you to elaborate the process for the same. Right now I dont have any punch file with me. Can you explain with the help of any punch file? Once that is clear, I will look for the program.
Also, Sir I found that transition dipole moment matrix in the TDDFT o/p file is of the size NSTATE X NSTATE. Can you explain how to analyse this? I find the x,y,z data corresponding to an i,j element. Does the magnitude of this dipole moment = sqrt(x^2+y^2+z^2)? Any help would be welcomed. If I plot this graph, what could be conveyed from this?

Kind Regards,

On Sat Sep 20 '14 1:28am, Alex Granovsky wrote
>Dear Siddheshwar,
>Dear Pavlo,

>internally, Firefly (and other QC codes) uses one-particle TDM to
>compute such properties like transition dipole moments/dipole
>velocities and oscillator strengths. These is no option at present
>to print out a computed one-particle TDM.


>for TDDFT, one-particle TDM can be recovered using an information
>found in the punch file. You will need to write small Fortran
>or C program for this.

>Kind regards,
>Alex Granovsky
>On Thu Sep 18 '14 8:37pm, Pavlo Solntsev wrote
>>TDM you can get for MCSCF/XMCQDPT jobs. I am not sure about DFT. By default TDM is not available in the output file. Probably, Alex may answer your question regarding DFT/TDDFT level of theory.

>>On Thu Sep 18 '14 1:36pm, Siddheshwar Chopra wrote
>>>Dear Pavlo,
>>>I read an article which used the Transition density matrix analysis. According to it, transition densities represent coherent electronic transitions between ground and electronically excited states.

>>>Some references:
>>>a) S. Mukamel, S. Tretiak, T. Wagersreiter, V. Chernyak, Science1997, 277,781 787;
>>>b) S. Tretiak, K. Igumenshchev, V. Chernyak,Phys. Rev. B2005,71, 033 201;
>>>c) S. Tretiak, S. Mukamel, Chem. Rev.2002, 102, 3171 3212;
>>>d) S. Tretiak, V. Chernyak, S. Mukamel,Chem. Phys. Lett.1996, 259,5561;
>>>e) K. I. Igumenshchev, S. Tretiak, V. Y. Chernyak,J. Chem. Phys.2007,127, 114902;
>>>f) Y. H. Li, C. A. Ullrich, Chem. Phys.2011, 391, 157 163.

>>>The transition-density matrix analysis helps in pointing out the section of structure/molecule from where the electronic transition mainly occurs.
>>>Also I found a paper which describes the relation between transition dipole moment and transition density.
>>>a) Mengtao Sun,Jianing Chen and Hongxing Xu, THE JOURNAL OF CHEMICAL PHYSICS 128, 064106 2008.

>>>In general transition density contains information about the spatial location of the excitation.

>>>Kind Regards,
>>>On Thu Sep 18 '14 5:01am, Pavlo Solntsev wrote
>>>>Dear Siddheshwar.

>>>>Could you please explain me what Transition density matrix stands for?


>>>>On Wed Sep 17 '14 9:45am, Siddheshwar Chopra wrote
>>>>>Dear Users,
>>>>>I wish to know about the determination of Transition density matrix. How do we extract it from the o/p data? Do we need to mention any special command to get the same? If no, then how to search for it in the o/p file? What all we can infer using it? Someone please throw some light on it.

>>>>>Kind Regards,

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