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["Wu Rongqin" <g0203654@nus.edu.sg>]

Well, I encountered similar things 1 year ago. Actually as long as the 
calculated cell does not belong to cubic system, this message appears. 
For HfO2 electronic and lattice dielectric, please refer to PRB, 65, 233106 
(2002).


-----Original Message-----
From: zfhou@mail.edu.cn [mailto:zfhou@mail.edu.cn] 
Sent: 2005年5月2日 0:40
To: forum@abinit.org
Subject: [abinit-forum] How to get rid of the warning "The dynamical matrix 
was incomplete : phonon frequencies may be wrong ..."

Dear abinit users,

I have tried to calculate the dielectric tensor of HfO2 with tetragonal 
structure containing 12 atoms or 6 atoms, using Hartwigsen-Goedecker-Hutter 
LDA psp for Hf and O. In my calculation, the cutoff energy is 35 Ha and the 
k-point mesh is 7 x 7 x 5. However the warning "The dynamical matrix was 
incomplete : phonon frequencies may be wrong ..." occured in output file. 
Except the increasment of cutoff energy, k-points and convergence tolerance, 
is there any other rule-of thumb to get rid of this warning?

I have tested to increase the k-point mesh and convergence tolerance, this 
warning can't be removed.
  
In addtion, I have used the same pseduopotentials and cutoff energy to 
calculate the cubic HfO2. Although I got a larger dielectric tensor than the 
values in PRB69,184301(2004)(G.-M.Rignanese, et al), there was no such waning 
in the calculation.

Your suggestions and helps will be greatly appreciated!
zhufeng

----------input file for tetragonal HfO2--------
ndtset  3

#Ground state calculation
  kptopt1   1          
  tolvrs1   1.0d-18      
    iscf1   5         

#Response Function calculation : d/dk
  rfelfd2   2         
   rfdir2   1 1 1    
    nqpt2   1
     qpt2   0.0 0.0 0.0  

  getwfk2   -1            
  kptopt2   2      
    iscf2  -3            
  tolwfr2   1.0d-18

#Response Function calculation : electric field perturbation and phonons
  rfphon3   1            
 rfatpol3   1 2         
  rfelfd3   3          
   rfdir3   1 1 1     

    nqpt3   1
     qpt3   0.0 0.0 0.0  

  getwfk3   -2          
  getddk3   -1         

  kptopt3   2          
  tolvrs3   1.0d-10
    iscf3   5         

#Definition of the unit cell
acell    6.7261613019E+00  6.7261613019E+00  9.7644094669E+00 
angdeg 90.0  90.0  90.0   

#Definition of the atom types
spgroup  137
ntypat 2    
znucl 72  8           
natom 6           
typat 2*1 4*2        
xred          0.0000000000E+00  0.0000000000E+00  0.0000000000E+00
              5.0000000000E-01  5.0000000000E-01  5.0000000000E-01
              0.0000000000E+00  5.0000000000E-01  1.9835156639E-01
              0.0000000000E+00  5.0000000000E-01  6.9835156639E-01
              5.0000000000E-01  0.0000000000E+00 -1.9835156639E-01
              5.0000000000E-01  0.0000000000E+00  3.0164843361E-01

#Definition of the k-point grid        
ngkpt 7 7 5       

#Definition of the SCF procedure
ecut  35.0         
nstep 60              
diemac 3.0       
nband 60
ixc  2 
----------------------END-------------------------------------