TDDFT for excited state energy

[matejhus]

Hi everyone

I'm trying to compute the excitation energies of a small system using TD-DFT. Following the instructions from the manual, I first ran the ground state calculation, followed by a TD-DFT step. However, I am unable to locate the excited state energy in the second output. This value does not seem to be printed.

I would appreciate a hint as to what I'm doing wrong.

Thanks!


calc 1 (on optimized structure)
INCAR created by Atomic Simulation Environment
ENCUT = 500.000000
POTIM = 0.100000
SIGMA = 0.050000
EDIFF = 1.00e-05
ALGO = Normal #TDHF=TD-DFT
GGA = PE
PREC = Normal
IBRION = 3
ISIF = 2
ISMEAR = 0
ISPIN = 1
NBANDS = 64 !must be triple
NSW = -1
IVDW = 11
LCHARG = .TRUE.
LWAVE = .TRUE.
LREAL = .FALSE.
LOPTICS=.TRUE.
LPEAD = .TRUE.

calc 2 (changes/additions)
ALGO = TDHF
LFXC = .TRUE.
AEXX = 0.0

[alexey.tal]

Hi,

The excitation energies should be written to the vasprun.xml file after the line <varray name="opticaltransitions">. Alternatively, you can extract the dielectric function, which is also written to vasprun.xml.

If you can't find this data, it probably means that something was wrong with the calculation. In such case, I would ask you to provide all the relevant files described in the forum guidelines.

[matejhus]

Thanks alexey.tal for a quick response. Turns out I was looking at a wrong file.