Herzberg-Teller term

Dear all,

I am currently simulating vibronic spectra including the Herzberg-Teller effect. At the end of the output file vibronic_spectra.log the HT terms associated with each normal mode are printed. However, it is not clear to me whether these terms are related to the complete Herzberg-Teller term, i.e. (dm/dQ) <i|Q|f>, or just to the derivative of the transition dipole moment, i.e. (dm/dQ). Moreover, are these terms expressed in atomic units?

Thank you for your help.


The original author of the vibronic code, Prof. WanZhen Liang, confirmed that the HT term is (dm/dQ) <i|Q|f>, not just dm/dQ.

Perfect! Thank you very much for your help.