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Re^2: Can we calculate Frequency dependent dielectric constant of any sample?

Siddheshwar Chopra
sidhusai@gmail.com

Dear Alex,
Thank you for the information. As per your input file, I ran the program to find polarizability of a molecule. I wish to ask that is it possible to give the FREQ(n) array for a range of 1MHz to 20GHz? Is it possible to get this frequency range in FIREFLY?

Regards,

On Tue Jun 18 '13 8:02pm, Alex Granovsky wrote
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>Dear Siddheshwar,

>dielectric constant is a macroscopic property.
>At microscopic level, we can compute frequency-dependent
>polarizabilities and hyper-polarizabilities. Having a certain
>model of the macroscopic body one can relate a microscopic
>properties such as polarizability to a dielectric constant.

>Below please find a sample file with computation of
>frequency-dependent polarizability for benzene molecule
>using PBE0 density functional. In brief, this is done
>using runtyp=TDHF and specifying some DFTTYP.
>If no DFTTYP is given, then these are indeed classical
>TDHF calculations, if DFTTYP is given then they in fact
>become TDDFT computations.

>

``` \$CONTRL SCFTYP=RHF DFTTYP=PBE0 runtyp=TDHF nosym=1 \$END
\$SYSTEM TIMLIM=300 MEMORY=3000000 \$END
\$BASIS  GBASIS=N31 NGAUSS=6 NDFUNC=1 NPFUNC=1 \$END
\$TDHF NFREQ=2 FREQ(1)=0,0.1 \$END
\$DATA
C6H6
Dnh       6

CARBON      6.0     -0.698164472         1.209256337         0.000000000
HYDROGEN    1.0     -1.241338149         2.150060743         0.000000000
\$END
```

>
>
>Kind regards,
>Alex Granovsky
>
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>On Fri Jun 14 '13 11:00am, Siddheshwar Chopra wrote
>---------------------------------------------------
>>Dear Sir,
>>I would be glad if you could throw some light on How to calculate the frequency dependent Dielectric constant using FIREFLY?? As far as I have read, DFPT is used to do the same... please help.

>>Regards,

Wed Jun 19 '13 2:24pm