Hello,
I am trying to compare the outputs of TDHF and TIMEEV runs (with VASP 6.6.1). The VASP Wiki indicates that, to bring the Casida results into closer agreement with time-propagation, one should increase ENCUTGW beyond its default value and set ANTIRES=2 in the Casida TDDFT calculation.
As an example, for a TDHF run that uses ENCUT=450 eV, the OUTCAR shows ENCUTGW=300 eV, and ENCUTGWSOFT=240 eV (exactly as per the defaults noted on the Wiki).
On the other hand, for the TIMEEV run, the output is a bit more cryptic: for ENCUT = 450 eV, the OUTCAR shows ENCUTGW=-1.6 and ENCUTGWSOFT=-1.6 -- it is not immediately obvious what the actual values are and, consequently, I am not able to port these defaults to the Casida run for consistency.
Any clarification is most appreciated!
Ashwin