Negative scissors operator

[lz dong]

Dear all,

When performing BSE calculations, we typically apply a scissor operator to increase the band gap to the GW value. However, in certain special cases, if we want to reduce the initial band gap, can this be achieved by applying a negative scissor operator (KfnQP_E and XfnQP_E)?

Best

[Daniele Varsano]

Dear lz Dong,

yes, you can use that two keywords to reduce the gap in the calculation of the response function and BSE kernel.

Best,

Daniele