Normalization of Daughter States

The commutation relations (42) can be used to normalize the A-electron states obtained by acting on (A — 2)-electron states with Kramers pair creation operators [8], Suppose that P) is a properly normalized (N — 2)-electron state which is annihilated by By, i.e., suppose that 

We would like to choose the normalizing constant a in such a way that the A-electron state 

In other words, A is the number of electrons in the subshell y in the parent state IP). This need not be zero, even though By annihilates IP). More generally, one can show 

This last relationship can be used to normalize the states obtained by creating successively larger numbers of Kramers pairs in a subshell until no more states with the symmetry and seniority of the parent state can be created by further filling of the sub shell. 

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