Nonlinear optic calculation

Hello everyone
I am a beginner of the ABINIT code and I am trying to repeat the calculation in the article ‘’. I am using the same type of pseudopotentials, structure, k-mesh, and cut-off energy as in the article, but my X(2) vs photon figure is different from Fig 6(left) in the article. The attachment is my input files and the X(2) image. Could you please give me some suggestions?

Best regards,

Yunfan (517 Bytes) (3.09 KB)
Abs X(2).png


you should try to converge things with respect to k point grid density and nband: I see you are using the same as in the paper but perhaps it’s not sufficient.

Your order of magnitude looks the same and Chi111 is similar, it’s the other peak structures which are different. Have you reproduced all of the linear stuff first?

You can ask the author for an example input in case there are subtleties or differences in the pseudopotentials you are using, or the structure.