[Pw_forum] Interatomic force constant

[Onaiwu Kingsley Nosa]

Dear Stefano,
I thank you for the prompt response to my question. Whenever and
wherever I need your assistance again I'll let you know.
Best wishes,
Kingsley Onaiwu

On 9/9/11, Stefano Baroni <baroni at sissa.it> wrote:
> Dear Mr. Onaiwu,
>
> Quantum ESPRESSO can calculate IFCs from first principles, and then it has
> small utilities for calculating phonon dispersions from the calculated IFCs.
> Of course, it does not make any sense to sense to "change" the IFCs
> calculated from first principles, because the ICFs are the *output*, not the
> input, of the calculations. Once the IFCs are calculated and stored, as
> said, they can be used to calculated vibrational dispersions. Nothing
> forbids to change the calculated IFCs for further reuse, provided one knows
> what one is doing, and why.
>
> This being said, it seems to me that the pw forum would be the ideal arena
> for discussions such as the present one. For that reason, I am forwarding my
> reply to your enquiry to the forum as well.
>
> Best regards,
>
> Stefano Baroni
>
> On Sep 8, 2011, at 11:33 PM, Onaiwu Kingsley Nosa wrote:
>
>> Dear Stefano,
>> I'm presently doing a phonon calculation of graphene in my Ph.D
>> research. Please, I'd want to know if there is any way that the
>> interatomic force constant can be changed in the Quantum espresso
>> code. I'd be grateful of any assistance in this regard.
>> Kingsley Onaiwu
>
> ---
> Stefano Baroni - SISSA  &  DEMOCRITOS National Simulation Center - Trieste
> http://stefano.baroni.me [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni
> (skype)
>
> La morale est une logique de l'action comme la logique est une morale de la
> pensée - Jean Piaget
>
>