[Pw_forum] phonon lifetimes

[Lorenzo Paulatto]

On Fri, 24 Feb 2012 03:29:07 +0100, Giuseppe Romano <romanog at mit.edu>  
wrote:
> I'm computing the anharmonic scattering time for bulk Silicon. While pw  
> and
> ph work as expected, d3 crashes. It seems there is some missing
> parameter. Is "fild0rho" necessary? Below are the scripts.


Dear Giuseppe,
there are several things missing in your calculation:
1. perform a pw.x calculation
2. perform a ph.x calculation at Gamma to produce fild0rho, store this  
file and do not overwrite it
3. another ph.x at the point q you want, this will produce fildrho
4. d3.x calculation with fildrho and fild0rho both set, and of course the  
point specified at the end of the input file

-- notes --
a. step 2 and 3 MUST be done in this orther
b. the d3 calculation MUST follow step 4 with no other calculations in  
between
c. the d3.x calculation will corrupt the phonon data (if using nlcc),  
store a copy of it

There is an example somewhere, it is example14 in QE 4.3.2, which pretty  
much shows the procedure.

bests


-- 
Lorenzo Paulatto IdR @ IMPMC/UPMC CNRS & Université Paris 6
phone: +33 (0)1 44275 084 / skype: paulatz
www:   http://www.impmc.upmc.fr/~paulatto/
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