Yambo Community Forum

Dear developers,

I have 2 questions regarding the TDDFT calculation.
1) The TDDFT kernels such as ALDA/LRC are supported for hybrid (HSE) ground state calculations?
2) I would like to perform a TDDFT spectrum calculation on top of hybrid functional ground state solution and obtain information about the transition dipole moments and the decomposition of the exciton wavefunction. Is it possible to select only a region of k-points around a high symmetry point (e.g. Gamma) to compute transitions between the CBM and some valence bands?

Best Regards,
Erik Perez

Dear Erik Perez,

1) support for hybrids in building the kernel is so far limited to TD-PBE0. TD-HSE is not implemented.
Here an example of TD-PBE0 calculations performed with yambo: https://journals.aps.org/prb/abstract/1 ... 107.115121
One remark. The long range interaction kernel, coming from the derivative of the non local exchange part of PBE0 is fully accounted for. Instead for the short range PBE part, only the LDA kernel is included, neglecting the gradient corrections.

2) After you solve the TD-PBE0 in transition space, you can inspect the excitonic wave-functions and check which are contributing to a specefic k-points reagion. For example you can plot them on the band srtucture using yambopy. However, the TD-PBE0 calculation must be computed on the whole k-grid

Best,
D,