Introduce Repulsive Gaussian Potential at atomic sites VASP

[sasant]

Hello,

I have been working on ab-initio modeling of InAs/Si interface. I wish to open band gap in InAs for this study. Using hybrid functional is out of scope due to large computational time. I tried with metaGGA, but metaGGA calculations do not converge for such a system.

I was planning to use modified pseudo-potential approach suggested in "Christensen, Phy. Rev. B, vol. 30, p.5753 (1984)". In this approach, repulsive Gaussian potential is introduced at atomic site. This potential primarily lifts up the position of CB edge at Gamma point. When used together with LDA pseudopotentials, this approach can open band gap in III-V materials

In earlier work, Yoon-Suk Kim et. al. simulated III-V materials with VASP using the above mentioned modified pseudo-potential approach. (See "Yoon-Suk Kim et.al. Phy.Rev.B 82, 205212 (2010)" ). Could you please tell me how we can incorporate these repulsive Gaussian potentials at atomic sites in the simulations in VASP?

Many thanks for your help!

Best regards,
Saurabh

[admin]

The tuning of the band gap using repulsive Gaussian potentials located on atoms
is implemented as MBJLDA method. Cf.
http://cms.mpi.univie.ac.at/vasp/vasp/m ... .html#4216
and some known issues
http://cms.mpi.univie.ac.at/vasp-forum/ ... LDA#p17147