[Pw_forum] Re: [Pw_forum] Re： Re: [Pw_forum] Problem of the underestimation of the frequency caused by matdyn.x

[yanmingma]

Dear Liyan,

Please check the corresponding masses for Ca and C as suggested by Paolo.

Regards




yanmingma
2006-10-10



发件人： li yan
发送时间： 2006-10-10 04:34:12
收件人： pw_forum at pwscf.org
抄送： 
主题： [Pw_forum] Re： Re: [Pw_forum] Problem of the underestimation of the frequency caused by matdyn.x


         i'm sorry to have make a mistake about my problem. The system is CaC6 instead of FeO . i select one of the dyn files, the  the frequencis at q point are:
 q = (    0.000000000   0.000000000   0.286236050 )
     omega( 1) =       1.432232 [THz] =      47.774442 [cm-1]
     omega( 2) =       1.432232 [THz] =      47.774442 [cm-1]
     omega( 3) =       3.262337 [THz] =     108.820586 [cm-1]
     omega( 4) =       3.262337 [THz] =     108.820586 [cm-1]
     omega( 5) =       3.587688 [THz] =     119.673169 [cm-1]
     omega( 6) =       8.461922 [THz] =     282.261207 [cm-1]
     omega( 7) =      12.447993 [THz] =     415.223105 [cm-1]
     omega( 8) =      12.447993 [THz] =     415.223105 [cm-1]
     omega( 9) =      13.116535 [THz] =     437.523408 [cm-1]
     omega(10) =      13.116535 [THz] =     437.523408 [cm-1]
     omega(11) =      19.159806 [THz] =     639.106575 [cm-1]
     omega(12) =      28.691164 [THz] =     957.040582 [cm-1]
     omega(13) =      29.038383 [THz] =     968.622620 [cm-1]
     omega(14) =      33.223897 [THz] =    1108.237267 [cm-1]
     omega(15) =      33.223897 [THz] =    1108.237267 [cm-1]
     omega(16) =      33.281138 [THz] =    1110.146637 [cm-1]
     omega(17) =      33.281138 [THz] =    1110.146637 [cm-1]
     omega(18) =      41.604039 [THz] =    1387.770602 [cm-1]
     omega(19) =      42.074591 [THz] =    1403.466608 [cm-1]
     omega(20) =      43.376807 [THz] =    1446.904149 [cm-1]
     omega(21) =      43.376807 [THz] =    1446.904149 [cm-1]
while in the matdyn.modes file, the frequencies of the modes at the same point becom
  q =       0.0000      0.0000      0.2862
     omega( 1) =       0.867379 [THz] =      28.932849 [cm-1]
     omega( 2) =       0.867380 [THz] =      28.932870 [cm-1]
     omega( 3) =       2.308488 [THz] =      77.003380 [cm-1]
     omega( 4) =       4.689393 [THz] =     156.422366 [cm-1]
     omega( 5) =       4.689394 [THz] =     156.422387 [cm-1]
     omega( 6) =       6.821788 [THz] =     227.551869 [cm-1]
     omega( 7) =       6.821788 [THz] =     227.551870 [cm-1]
     omega( 8) =       8.276312 [THz] =     276.069874 [cm-1]
     omega( 9) =       8.276312 [THz] =     276.069882 [cm-1]
     omega(10) =      10.491723 [THz] =     349.968534 [cm-1]
     omega(11) =      13.134275 [THz] =     438.115167 [cm-1]
     omega(12) =      15.696771 [THz] =     523.591396 [cm-1]
     omega(13) =      15.903656 [THz] =     530.492373 [cm-1]
     omega(14) =      18.187294 [THz] =     606.666874 [cm-1]
     omega(15) =      18.187294 [THz] =     606.666875 [cm-1]
     omega(16) =      18.222317 [THz] =     607.835092 [cm-1]
     omega(17) =      18.222317 [THz] =     607.835098 [cm-1]
     omega(18) =      22.768578 [THz] =     759.483060 [cm-1]
     omega(19) =      23.037730 [THz] =     768.461058 [cm-1]
     omega(20) =      23.744563 [THz] =     792.038631 [cm-1]
     omega(21) =      23.744563 [THz] =     792.038632 [cm-1]  
that is to say that all the frequencies are underestimated after using q2r.x and matdyn.x. what's the prpblem with it?
Thank you very much. 
ka <wierzbom at ts.infn.it> 写道：
On Mon, 9 Oct 2006, Paolo Giannozzi wrote:

> On Oct 9, 2006, at 16:15 , li yan wrote:
>
>> I calculated the phonon frequencies of FeO for a list of generic
>> q vectors with q2r.x and matdyn.x. In the FeO.dyn files , the highest 
>> frequency is about 43 THz, while it is about 22 THz in the matdyn.modes 
>> file and FeO.freq file. What problems may occur in the the process?
>
> wrong masses? Paolo
>

What q-points and modes of FeO? Are you sure about units, THz?

Gosia


> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>
_______________________________________________
Pw_forum mailing list
Pw_forum at pwscf.org
http://www.democritos.it/mailman/listinfo/pw_forum





Mp3疯狂搜-新歌热歌高速下 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20061010/cb370057/attachment.html>