Two subroutines to calculate Born Effective Charges

[whzhang]

Dear all,

I am trying to learn Born Effecitve Charge calculations, when I was reading linear_response.F, I found there are two subroutines, i.e. LRF_MAIN and LR_MAIN both can give Born Effective Charges. I am just wondering what is the main physical difference between these two subroutines? And if they are different, which one is more accurate (in principle and in practice)?

Thank you!

[whzhang]

Dear admin, I thought the authors may give some comments on it. Thanks.

Best Regards,
Wenhua