[DFTB-Plus-User] frequency calculation in DFTB+

[Anne-Marie Kelterer]

Hallo Benjamin,

you were the first who answered  :)

Harmonic frequencies would be enough for the starting.
We want to know, whether the DFTB+ optimizations would give
appropriate geometries for some organic material, and
for this, we would like to compare with normal DFT and
also make some QCE thermodynamic evaluation for comparison.
This would afford the harmonic (better anharmonic, but
this is too time-consuming in DFT) frequencies.

About autocorrelation, I don't know enough to use,
but maybe you can send me some reference, where I can read
that topic. It is also interesting for the future,
after MD calculations, because we want to put our material
in some MD later.

Hope, that the new DFTB+ comes out soon,

best regards, Anne-Marie Kelterer

Quoting Ben Hourahine <benjamin.hourahine at strath.ac.uk>:

> Hello Anne-Marie,
>
> I'm not sure if anyone replied to your email. Do you want
> harmonic frequencies or from autocorrelation?
>
> dftb+1.1 will have Hessian calculation for harmonic modes
> implemented. Hopefully the release time for this will be
> in the next few weeks. Otherwise, if you have a long MD
> trajectory I can send you some code to calculate the
> velocity autocorrelation.
>
> Anne-Marie Kelterer wrote:
>> Dear users, dear developers,
>>
>> is there a possibility to calculate frequencies in DFTB+ ?
>>
>> I read something in the archives, but would need the program.
>>
>> Thanks, Anne-Marie
>>
>> --
>> ----------------------------
>> Ass.Prof. Dr. Anne-Marie Kelterer
>> Institute of Physical and Theoretical Chemistry
>> Graz University of Technology
>> Technikerstr.4/I, A-8010 Graz, Austria
>> Tel: +43 316 873 8223, Fax: +43 316 873 10 8223
>> kelterer at tugraz.at
>>
>>
>> _______________________________________________
>> DFTB-Plus-User mailing list
>> DFTB-Plus-User at dftb-plus.info
>> http://www.dftb-plus.info/mailman/listinfo/dftb-plus-user
>
> --
>      Dr. B. Hourahine, SUPA, Department of Physics,
>    University of Strathclyde, John Anderson Building,
>           107 Rottenrow, Glasgow G4 0NG, UK.
>     +44 141 548 2325, benjamin.hourahine at strath.ac.uk
>    The University of Strathclyde is a charitable body,
> registered in Scotland, with registration number SC015263
>
> _______________________________________________
> DFTB-Plus-User mailing list
> DFTB-Plus-User at dftb-plus.info
> http://www.dftb-plus.info/mailman/listinfo/dftb-plus-user
>



-- 
----------------------------
Ass.Prof. Dr. Anne-Marie Kelterer
Institute of Physical and Theoretical Chemistry
Graz University of Technology
Technikerstr.4/I, A-8010 Graz, Austria
Tel: +43 316 873 8223, Fax: +43 316 873 10 8223
kelterer at tugraz.at