Roothaan equation (F*C = S*C*E)
Clicked A Few Times
8:21:49 AM PDT - Sun, Jul 21st 2013
Hi,

When dealing with the Roothaan equation in hf or dft theory (F*C = S*C*E), how does the NWChem code transform this generalised eigenvalue equation to eigenvalue equation (F'*C' = E*C') during the scf calculation?

Thanks,

Forum Vet
11:01:20 AM PDT - Mon, Jul 22nd 2013
The routines dealing with the F'=X'*F*X transformation and subsequent diagonalization are in the file
$NWCHEM_TOP/src/nwdft/scf_dft/dft_diagn.F
When canonical orrthogonalization is needed, the code used sits in
$NWCHEM_TOP/src/nwdft/scf_dft/dft_canorg.F

What we implemented in NWChem for the two steps above follows pretty close what you can find in several
articles and books (one good reference would be Szabo and Ostlund)

Cheers, Edo


Forum >> NWChem's corner >> NWChem functionality