Multiwfn forum / Question about how to simulate the fluorescence spectrum in ORCA

Re: Question about how to simulate the fluorescence spectrum in ORCA

dummy@example.com (jano) — Sun, 12 Oct 2025 12:20:48 +0000

Thanks for your reply, Professor. But if we are to simulate fluorescence spectrum I thought the starting geometry should be an optimized excited state geometry, correct?

Re: Question about how to simulate the fluorescence spectrum in ORCA

dummy@example.com (sobereva) — Sun, 12 Oct 2025 12:13:11 +0000

Hello,

The developer knows more than me. At least, I found the simulated emission spectrum in this way is correct. Maybe it was designed in that way.

Question about how to simulate the fluorescence spectrum in ORCA

dummy@example.com (jano) — Sun, 12 Oct 2025 08:58:37 +0000

Dear Prof. Lu,

In the ORCA tutorial
https://www.faccts.de/docs/orca/6.0/man … l/esd.html
in the part that talks about the simulation of fluorescence spectrum of benzene with vibronic effects (6.18.2. Fluorescence Rates and Spectrum), the optimized ground state geometry was used in the input file
*XYZFILE 0 1 BEN.xyz.
However, shouldn't we use the optimized "S1" excited-state geometry, that is,
*XYZFILE 0 1 BEN_S1.xyz?

Many thanks in advance.

Jano.