Exchange interactions (J) and axial zero-field splitting (D) parameters for 1–8 derived from a simultaneous fit of the susceptibility and magnetisation data employing spin-Hamiltonian (1).

	J (cm−1)	|D| (cm−1)
1	J Ni–Ni = −0.078 (no MX4 guest – fixed for 2–8)	|DNi| = 1.575 (no MX4 guest – fixed for 2–8)
2	J Ni–Mn = −0.041	Neglected for MnII
3	J Ni–Fe = −0.068	Neglected for FeIII
4	J Ni–Fe = −0.084	Neglected for FeIII
5	J Ni–Co = −0.005	|DCo| = 2.37
6	J Ni–Co = −0.001	|DCo| = 6.30
7	J′Ni–Ni = −0.476	|D′Ni| = 85.5
8	J Ni–Cu = −0.062	Neglected for CuII