Compound 1-Gd•0.5MeCN exhibits a constant MT value of 8.10 cm 3 K mol -1 across the entire temperature range, consistent with the spin only ground 8 S7/2 term for Gd 3+ . Ab initio calculations (vide infra) afford excellent reproduction of the experimental data in all cases. Field dependent, variable temperature magnetization data were collected at 2, 4, and 6 K with an applied field from 0 to 7 T for all compounds (Figures ). Magnetization versus field plots for 1-RE•0.5MeCN (RE = Tb, Dy, Ho, Er, Tm and Yb) approach values at 2 K and 7 T that are consistent with the theoretical values (Table ). The experimental data are in good agreement with the curves calculated ab initio, vide infra. The profiles for 1-Eu•0.5MeCN, and 1-Tm•0.5MeCN exhibit a linear dependency for Eu 3+ ions, consistent with a non-(or weakly-) magnetic ground state, however, the measured profiles show some curvature with applied field, suggesting a slight population of excited magnetic state. The profiles from 1-RE•0.5MeCN (RE = Sm, Gd, Tb, Dy, Ho, Er, and Yb) all saturate at 7 T and 2 K. phase alternating current (AC) magnetic susceptibility in the absence of an external DC field.