QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: qweasel on February 21, 2017, 02:38

Title: Why I don't see LSDA under "Exchange correlation"?
Post by: qweasel on February 21, 2017, 02:38

I'm following your paper in PRB (https://journals.aps.org/prb/abstract/10.1103/PhysRevB.85.165442), where you used LSDA for Ni-graphene interface.

According to the NiO tutorial (https://quantumwise.com/documents/tutorials/latest/NiO_LDA_U/index.html/chap.crystal.lda.html), LSDA is supposed to be listed under "Exchange correlation". However I only have LDA, GGA and MGGA there.

Title: Re: Why I don't see LSDA under "Exchange correlation"?
Post by: Jess Wellendorff on February 21, 2017, 08:17

You need to "turn on" spin-polarization to get the options LSDA and SGGA. Select "Polarized" in the drop-down menu named "Spin".

Title: Re: Why I don't see LSDA under "Exchange correlation"?
Post by: qweasel on February 21, 2017, 13:13

Can you please briefly explain why spin polarization is needed here in the first place?

Title: Re: Why I don't see LSDA under "Exchange correlation"?
Post by: Jess Wellendorff on February 21, 2017, 15:13

Bulk nickel and compounds containing nickel atoms are usually spin-polarized in the electronic ground state. You need spin-polarized DFT to capture this.