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Re^6: Help needed with the Transition density matrix determination and analysis....

Siddheshwar Chopra
sidhusai@gmail.com


Dear Alex Sir,
I would be really grateful if you could throw some light on the transition density matrix calculation. Is it possible to determine the matrix from TDDFT output file? IF yes then I would attach one file. Kindy let me know Sir.

Kind Regards,


On Sat Sep 20 '14 8:10am, Siddheshwar Chopra wrote
--------------------------------------------------
>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.

>>@Siddheshwar:
>>

>>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
>>----------------------------------------------
>>>ok,
>>>
>>>
>>>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.

>>>-Pavlo.
>>>
>>>
>>>
>>>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?

>>>>>-Pavlo

>>>>>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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