I would like to be able of calculate the different elements of the matrix in the case of a nucleus with l=1, but I don’t really know from where to start… I have written down the Hamiltonian, but there are several parts which I don’t know the value, like I+^2 and I-^2, Iz^2 and I^2. I don’t think it must be difficult, but it would be great to see a solved example to understand how to do it in future cases.