Table 2.

Number of Coordination Sites for Water Molecules (q), Enthalpy of Activation, Mn–¹⁷O Hyperfine Coupling Constants (A_O/ℏ), and Water Exchange Rates at T = 310 K (k_ex³¹⁰)

Cas	q calc	ΔH‡ [kJ/mol]	A/h [x107 rad/s]	kex310 (×108 s−1)
MnPyC3A-BPEN	0.9 ± 0.2	33 ± 0.50	2.8 ± 0.10	0.7 ± 0.1
MnPyC3A*	1	37.2	2.9	1.0