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[tony lee <tonymidlee@hotmail.com>]

Dear all,

I am pretty much a newbie in ABINIT. I am trying some calculations of the
dielectric funciton for some ternary chalcopyrite type compounds(space group
D2d). 

First, I think it is uniaxial crystal, so it should have two distinct
dielectric functions(imaginary part): \epsilon_xx=\epsilon_yy and \epsilon_zz,
but from what I got,  those three are different in shape and amplitude,
especially \epsilon_xx(amlost double in amplitude).  I checked the output 
file,
the only warning I think matters is the following:  
WARNING : Localization tensor in reciprocal space incomplete,
            transformation to cartesian coordinates may be wrong.
what does it mean?

So here are my questions: 
1. How to specify the optical axis? or it is done automatically? 
2. what did I do wrong in the calculation? How to get rid of the warning
message? 
3. I did not use many k-points and bands due to limited resources, how would
that effect the outcome? My guess is that it should not cause any symmetry
problems, i.e. I should still get \epsilon_xx=\epsilon_yy and \epsilon_zz two
distinct dielectric functions, right? 

Any help is greatly appreciately!

Best Regards,

Tony