I am extracting J and K matrices from psi4 using JK build. I am using SCF type ‘DF’. Fock matrix constructed from these extracted J and K matrices is not matching with the fock I am directly getting from psi4 using wfn.Fa(). Kindly suggest where could be the possible error or I am missing something in the calculations.
You are missing the core Hamiltonian contribution to the Fock matrix
H_core has been added. But still it is not same.
You have not specified the type of calculation. If you are doing DFT, the Fock matrices will obviously not match with Hartree-Fock.
Thank you for pointing it out. Actually, there was issue with coefficients I was supplying to JK class, one set was converged coefficients while the another was without SCF.