QuantumATK Forum
QuantumATK => General Questions and Answers => Topic started by: dibakariitm on January 24, 2017, 12:17
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Hi,
I am trying to calculate band structure of Germanium with GGA+U with Hubbard parameter U for P and D orbitals (Up=-3.7 & Ud=-0.5) as given in the paper
"The effects of uniaxial and biaxial strain on the electronic structure of germanium" http://www.sciencedirect.com/science/article/pii/S0927025615006709
I am using HGH pseudopotential with GGA.PBE Tier 4 basis set as suggested by Umberto in this post http://quantumwise.com/forum/index.php?topic=3202.0 (http://quantumwise.com/forum/index.php?topic=3202.0).
But the simulation doesn't converge after 100 steps to the required Tolerance. Do I need to increase the Density Mesh Cutoff to some higher value from current value of 75 Hatree. Will that help.
Also I am using ATK 2015.1 so I don't have SG15 pseudopotential which was introduced in ATK 2016. So I am not able to use PseudoPotential Projector Shift (PPS) method as suggested by Jess here
http://quantumwise.com/forum/index.php?topic=4275.0 (http://quantumwise.com/forum/index.php?topic=4275.0)
Any suggestions will be greatly appreciated. I am attaching the script .
Thanks.