QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Jenny on September 30, 2013, 20:19

Title: how to choose Pseudopotential
Post by: Jenny on September 30, 2013, 20:19

Hello.

Recently, I tried to relax my unit cell. And I found if I used different pseudopotential and basis set, the optimized geometry would be different with same initial configuration of unit cell. For NC-HGH I used Tier 5 as basis set and for NC-FHI I used DoubleZetaPolarized. May I ask what's the difference between NC-FHI and NC-HGH? If I'd like to optimize the geometry and calculate the transmission spectrum of CNT and Cu composite, which pseudopotential should I use in these situation?

Thanks.

Jenny

Title: Re: how to choose Pseudopotential
Post by: kstokbro on October 5, 2013, 00:31

Both are norm conserving pseudo potentials. Usually the hgh are harder, thus you need a higher mesh cutoff for the hgh pseudo potentials.