[QE-users] one question about the matrix element calculation

[Yu, Jingjing]

Dear QE community members,

I am a beginner to do the DFT calculation. I have one question regarding 
to extracting matrix elements of the momentum operator between the 
valence and conduction bands wrriten in the file of "p_avg.dat".

I am wondering if the corresponding matrix elements along the x, y, z 
directions should be that same if the crystal structure of material is 
cubic (isotropic)?

Thanks a lot!

Best regards,
Jingjing Yu