The ABINIT Users Mailing List ( CLOSED )

[张 <zhangting@pku.edu.cn>]

Dear ABINIT users:

     I'm a beginner of ABINIT code, and I'm testing a phonon 
dispersion calculation using graphite system with ABINIT code. I 
followed the Tutorial lesson which name is "ABINIT,second lesson on 
response functions(RF2)", and replaced the data in trf2_x.in with data 
of graphite. The DDB files are obtained with the attached "phonon.in" 
file, which just follows the trf2_1.in file, and the results are 
summarized with MRGDDB code in the attached "graphite.ddb.out" file. 
But when I use ANADDB code to perform a phonon dispersion calculation
(the input file is "phononANADDB.in"), the code always escape with 
such error message:
  
   " symdm9 : ERROR -
  Informations are missing in the DDB.
  The dynamical matrix number     2 cannot be built,
  since no blok with wavevector    8.333333E-02    0.000000E+00    
0.000000E+00
  has been found.
  Action : add the required blok in the DDB, or modify your input file.

 leave_new : decision taken to exit ..."

     What does this mean? and how to avoid such an error in my 
calculation configuraion? I think that the problem is because of the k-
point configuration, but I don't know exactly the meaning of the k-
point setup keywords such as "shiftk" ....Why need such a keyword? 
what dose it mean? The explanation of this keyword is somewhat not 
very clear I think.

     And another question: there may be imaginary frequency in the 
phonon dispersion of graphite and CNTs calculated with DFT, can ABINIT 
code avoid this problem? or how to get rid of such annoying imaginary 
frequencies?

     If there are any other mistakes in my calculation configuration, 
don't hesitate to point out. Thanks very much!


                                                               Zhang 
Ting
                                                               
Apr.11th 2006

Attachment: graphite.ddb.out
Description: Binary data

Attachment: phonon.in
Description: Binary data

Attachment: phononANADDB.in
Description: Binary data