# Transition dipole moment of diatomic molecules

1. Apr 11, 2015

### sams

Hello Everyone,

A little question regarding the TDMs between two different electronic states of a diatomic molecule. If I am calculating the TDM from state A to state B, is it the same if we are calculating the TDM from state B to state A? Are these two transitions the same?

Thank you so much in advance?

2. Apr 12, 2015

### DrDu

Almost. The dipole moment operator is hermitian. So the TDM from A to B is $\langle B|d|A \rangle$ while the TDM for B to a is $\langle A |d| B \rangle=(\langle B|d|A \rangle)^*$, i.e. the complex conjugate.

3. Apr 13, 2015

### sams

Thank you very much DrDu for your help.