[Wien] mBJ gap GaAs

[Zhu, Jianxin]

Dear Dr. Tran, 

Can I use the -so option together with the mBJ functional?

In the UG, I see that (i) the -so option cannot be used together with -hf;
(ii) the -so option seems to be ok together with -eece at the expense that
-eece can be used only for spin-polarized calculations.
Please correct me if I'm wrong.

Thanks, 

Jianxin 



On 4/15/14 12:51 AM, "tran at theochem.tuwien.ac.at"
<tran at theochem.tuwien.ac.at> wrote:

>Hi,
>
>yes, 1.63 eV is the value that you should obtained with mBJ. This value is
>in much better agreement with experiment than LDA or PBE, but you should
>not expect perfect agreement with experiment. However, by varying
>manually the value of c [Eq. (3) of PRL 102, 226401 (2009)] you can get
>more or less any value of the band gap that you want (an increase of
>c leads to an increase of the band gap). For this, you have
>to specify yourself the values of alpha, beta and e in case.in0abp
>(c=alpha and choose 0 and 1 for beta and e, respectively).
>You can find some explanations at the very end of Sec. 4.5.9 in the user's
>guide.
>
>F. Tran
>
>On Tue, 15 Apr 2014, sollebac wrote:
>
>> Dear wien2k users,
>> Im trying to calculate the gap mBJ  of GaAs as an example following the
>> user-guide. Everything finished ok  but the value that  I got is 1.63
>>eV  at Gamma,  while the experimental value are  ~1.52 (300K)  and ~1.42
>>(0K).  How can i
>> get close value to experimental?  i mean how can i converge the value
>>(1.63)  to get the best value close to experimental?  the k-points are
>>560 IBZ and is
>> not-spin-polarized.
>> thank in advance.
>> Jose Luis       
>>