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[qmhu@imr.ac.cn]

Dear Abinitioners,
I'm very interested in the alchemical mixing of psps feature implemented in 
abinit 3.4.3. I have done some tests on it, and encontered some problems.

1. For disordered Ti(50%)Zr(50%) and Ti(50%)Nb(50%), it gives reasonable 
equilibrium lattice constants, but the calculated heats of formation is 
considerablely large (about 9eV for TiZr and 10.2eV for TiNb, being 
endothermic). I have no idea about the reliability of the calculated heats of 
formation.
For disordered Ni(50%)Al(50%) and Ti(50%)Ni(50%), it gives unphysical 
equilibrium lattice constants and total energies. It may be reasonable 
because  disordered TiAl and TiNi do not exist at low temperature. 
Therefore, can I conclude that the alchmeical mixing of psps is only 
applicable for the elements with similiar electronic structure, or say, for 
the elements that can form disordered solid solution? 

2. The problem mentioned previously by Lilia Boeri is not resolved in the 
binary PC version of 3.4.3.  It still gives wrong "occ".

Q. M. Hu
qmhu@imr.ac.cn