plain wave DFT basics

External optional components of Abinit (BigDFT, Wannier90...) and codes using/providing data from/to Abinit (AtomPAW, ONCVPSP, EXC, DP, Yambo...)

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R_S
Posts: 7
Joined: Mon Feb 15, 2010 9:27 pm
Location: Russia

plain wave DFT basics

Post by R_S » Thu May 06, 2010 5:35 pm

Hi everyone.
I'm a newbie in DFT so all my questions are related to the basics of the method. In order to understand the way abinit works I need to understand the main principles of plain wave dft. So here is scenario of the calculations which is used, I think, to calculate solids' properties. Tell me if I'm wrong anywhere.

1. Take the 1-st electron under consideration and choose 1-st k-point
1a. Calculate 3 potentials in the reciprocal space (E_ion, E_Hartree, E_XC)
1b. Set E_cutoff (this defines how many waves will be in the expansion of the Bloch wave)
1c. Calculate the components of the Hamiltonian matrix and diagonalize it to find the energy of the state under consideration
1d. Go to the 2-nd k-point and perform 1a-1c, ..., go to the last k-point and perform 1a-1c
2. Take the 1-st electron and perform 1
...
i. Take the last electron and perform 1

I understand this is not a detailed description of the process, but I hope it shows the main stages. So tell me pease if I'm wrong or right.

Thanks in advance!

gonze
Posts: 412
Joined: Fri Aug 14, 2009 8:29 pm

Re: plain wave DFT basics

Post by gonze » Thu May 06, 2010 7:08 pm

Dear R_S

As mentioned in
http://www.abinit.org/documentation/hel ... lcome.html
you should read some basic material about DFT + planewaves.

Best regards,
X

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