output XC matrix

[maki49]

Output the XC matrix in Kohn-Sham orbital representation $V^\text{xc}_{ij}=\braket{\psi_i|\hat{V}^\text{xc}|\psi_j}$ , useful for GW calculation.

[kirk0830]

wow fantastic, ABACUS will be capable to do GW calculation later? That will provide a in-built calibration of ABACUS TDDFT predicted optical spectrum results