In harmony with the observations with Nd-complexes, for Yb-complexes also, the NPA charge on Ybcenter, for a particular coordinated complex decreases with the increase of PF6 -coordination. Here, the difference of NPA charge between Yb-5-PF6 -and Yb-6-PF6 -complexes is found to be negligible. Similar to Nd-complexes, here also, with the increase of CN, the NPA charge on the Yb-center decreases. As shown in Table , for Yb-4-PF6 -complexes, the NPA charge on the Yb center decreases from 1.57 to 1.48 to 1.35 to 1.14 on going from 8CN to 9 CN to 10CN to 12CN.