Perturbation Calculation for H2 Energy Shift

We now calculate the expectation value of \bgroup\color{black}$H_2$\egroup. We will immediately use the fact that \bgroup\color{black}$j=\ell\pm{1\over 2}$\egroup.

\left<\psi_{njm_j\ell s}\left\vert H_2\right\vert \psi_{njm_j\...
\qquad \matrix{ j=\ell + {1\over 2} \cr j=\ell -{1\over 2} }

Note that in the above equation, we have canceled a term \bgroup\color{black}${\ell\over\ell}$\egroup which is not defined for \bgroup\color{black}$\ell=0$\egroup. We will return to this later.

Jim Branson 2013-04-22