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["zaq Liu" <iloveabinit@gmail.com>]

Dear Dr.Xavier,

Thank you for your help!
I do not find anomalously high value in for  perturbation.
I also tried to using iscf=2,3,7, but the result is same.
The system I calculate is PbFCl (insulating).
I try to calculate similar system ,like PbFBr and SrFBr, der
obtaining the very similar result.
I attach the calculate the phonon dispersion as an attachment.
I wonder if there's some factor should be considered futher.
Thank you very much!

B LIU




2006/9/26, Xavier Gonze <gonze@pcpm.ucl.ac.be>:
> On 25 Sep 2006, at 18:27, iloveabinit@gmail.com wrote:
>
> Dear Dr.Xavier,
>
> Thank you for your kind suggestion.
> I also calculated it using nband=28, however, the result is same.
>
> Too bad ...
>
> I find a warning as following after the calculation for DATASET 2.
> I don't know its meaning and is it related to my problem ?
>
> It is not at all related to your problem. For your information,
> see Sgiarovello et al, PRB64, 115202 (2001).
> You have to examine all the sequences of SCF steps , like
>
>       iter   2DEtotal(Ha)       deltaE(Ha) residm    vres2
>  ETOT  1   6.5156051312863    -1.464E+01 1.146E-02 1.947E+02
>  ETOT  2   5.0216331638978    -1.494E+00 9.267E-04 2.027E+00
>  ETOT  3   5.0082678671217    -1.337E-02 4.772E-06 7.929E-02
>  ETOT  4   5.0078677958105    -4.001E-04 1.980E-07 2.712E-03
>  ETOT  5   5.0078558860285    -1.191E-05 6.103E-09 5.074E-05
>  ETOT  6   5.0078557520180    -1.340E-07 1.258E-10 9.613E-06
>  ETOT  7   5.0078557017091    -5.031E-08 2.768E-11 3.841E-07
>  ETOT  8   5.0078557001188    -1.590E-09 2.983E-12 6.089E-09
>
> and see whether for some perturbation, vres2 does not stay
> at an anomalously high value. If so, identify all such perturbations.
> Then, try do redo these perturbations with other values of iscf,
> maybe also a bigger nline, nband ...
>
> Also, you should be sure that your material is indeed insulating
> (see the input file of your previous mail), and not metallic !
>
> Good luck,
> Xavier Gonze

Attachment: phonon dispersion.PDF
Description: Adobe PDF document