[Wien] New exchange-correlation potential

[yhzhao]

Dear Prof. Pblaha,

I have tried to calculate something using the new exchange potential
with indxc=50 as suggested by the usersguide. At first I want to repeat
some data given by PRL 102, 226401 (2009), for example, the band gap of
GaAs. I can get a band gap of 0.7 eV for GaAs, which is much better than
0.3 eV of lda, but not much better than the value given by you in PRL
102, 226401 (2009). In the calculation, I use the experimental lattice
constant. The k-grid have been increased as dense as 20x20x20 and RKmax
as large as 9.0.

Is there any adjustable parameter for the MBJ calculation? Thanks.

Regards,

yonghong