Chapter 11, Problem 11F.2BE

Interpretation Introduction

Interpretation:

The levels of the term for the ground electronic state of ${\text{O}}_2^{-}$.

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.

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

The levels of the term are denoted by the total electronic angular momentum.  The level of the term is denoted by $\Omega$ and is the sum of orbital part and spin part.