20.7.2 Matrix elements over two-electron operators

EXPEC2, $oper_1,oper_2,\ldots,oper_n$
TRAN2, $oper_1,oper_2,\ldots,oper_n$

Calculate transition matrix elements for two-electron operators. This is presently only useful for angular momentum operators. With EXPEC2 only diagonal matrix elements will be computed. For instance

TRAN2,LXX

calculates matrix elements for $L_x^2$

TRAN2,LYY

calculates matrix elements for $L_y^2$

TRAN2,LXZ

calculates matrix elements for $\frac{1}{2}(L_xL_z+L_zL_x)$

TRAN2,LXX,LYY,LZZ

calculates matrix elements for $L_x^2$, $L_y^2$, and $L_z^2$. The matrix elements for the sum $L^2$ are also printed.