Nuclear tensor operators, definition

In O Eq. 11.151 we have introduced the moment of inertia tensor I and we have used the definition of as given in OEq. 11.149, which is applicable both when using London orbitals and when using conventional basis sets. Both the nuclear positions and magnetic dipole operators are defined with respect to the center of mass of the molecule, as this is the point about which the molecule rotates. 

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