Chapter 11, Problem 11F.2P

Interpretation Introduction

Interpretation:

The allowed electric-dipole transitions to the excited state from the ground state of homonuclear diatomic halogen anions has to be stated.

Concept introduction:

A term symbol describes the orbital, spin and total angular momenta of an electronic state.  The symbol $L$ represents the vector sum of orbital angular momentum.  The symbol $S$ represents the vector sum of spin angular momentum.  The symbol $J$ represents the total angular momentum.  Therefore, the term symbol is represented as given below.

${}^{2S+1}{L}_J$

In case of diatomic molecules, the term symbol is given by the formula as shown below.

${}^{2S+1}{\Lambda }_{\Omega }$.