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["Zhenhua Zeng" <myid520@163.com>]

Hello Everyone,

I'm callculating phonon of Pb(111) slab: 6 ML Pb with a vaccum about 12 \AA,
I found that
[1] the result printed out in the out file are not consistent with the 
results of anaddb.
[2] I.e. the results in out file seem meaningless.

For example the phonon at gamma  point:
out file(cm-1): 3.754035E+01  3.922919E+01  3.951580E+01  4.177673E+01 ....
anaddb  (cm-1): almost zero   almost zero   almost zero   about 1.0E+01 ....

anaddb gives three acoustic mode at gamma point, which seem more reasonable.
so two question there:
[1] where the inconsistent comes from?
[2] why anaddb can give a 'reasonable' result, even though frequencies in the 
out file are so bad?

There seems have a statement that anaddb may give different result from 
frequencies given in out file in the tutorial files, but i can not found it 
anymore.
Did someone also pay attention on this statement?

key parameters are as following :
LDA_PP 82pb.4.hgh
ixc    1
ecut   20
ngkpt  12*12*1
tsmear 0.001
nline  20
tolmxf 5.0d-5  (for GS, the lattice constant is also fullly optimized with 
this criteria)
tolvrs 1.0d-18 (for GS)
tolvrs 1.0d-8  (for RF) 

These parameters are ok for the phonon calculation of bulk  Pb.

Your helps are greatly appreciated!
                                
Best Wishes
Zhenhua Zeng