where "CT" stands for "charge transfer" and indicates that the model space includes up to the qth local eigenstate only if the number of electrons in the given fragment in the given rootspace differs from that in the reference rootspace; otherwise, only the ground eigenstate of ĤPK is included. Such calculations are indicated in the text by the Roman subscript CT on the integer q value; for instance "LASSI[1, 5 CT ]."