ffsim.spinful_to_spinless_rdm2¶ ffsim.spinful_to_spinless_rdm2(mat_aa, mat_ab, mat_bb)[source]¶ Convert a spinful 2-RDM to a spinless 2-RDM. Parameters: mat_aa (ndarray) – The alpha-alpha part of the 2-RDM. mat_ab (ndarray) – The alpha-beta part of the 2-RDM. mat_bb (ndarray) – The beta-beta part of the 2-RDM. Return type: ndarray Returns: The 2-RDM as a single tensor in spinless format.