Table 3. EPR Parameters of the Components Obtained by the Simulation of Room Temperature (Isotropic Parameters) and 77 K (Anisotropic Parameters) Spectra Measured in Solutions Containing Cu²⁺-DO4S, Cu²⁺-DO3S, and Cu²⁺-DO2A2S and Suggested Coordination^a.

	isotropic parametersb		anisotropic parametersc
	g0	A0 (×10–4 cm–1)	g⊥ or gx, gy	g∥ or gz	A⊥ or Ax, Ay (×10–4 cm–1)	A∥ or Az (×10–4 cm–1)	calculateddg0,calc	suggested coordination
L = DO4S
CuL2+(1)	2.091	71.7						[4N]
CuL2+(2)	2.103	63.6	2.048, 2.058	2.209	20.3, 23.5	171.2	2.105	[4N]Sax
L = DO3S
Cu2+	2.196	34.9	2.085	2.423	11.8	127.2	2.197
CuL2+(1)	2.093	74.0	2.036	2.184	15.6	179.3	2.085	[4N]
CuL2+(2)			2.048, 2.058	2.209	20.3, 23.5	171.2	2.105	[4N]Sax
L = DO2A2S
Cu2+			2.085	2.423	11.8	127.2	2.197
CuLH22+(1)			2.066	2.257	11.5	158.1	2.129	[3N,S]
CuLH22+(2)			2.058	2.214	28.7	164,7	2.110	[4N]Sax
CuLH+			2.060	2.234	25.8	161,5	2.118	[3N,O]Nax
CuL			2.075	2.272	24.5	142.8	2.141	[2N,2O]2Nax
L = Cyclene
CuL			2.040, 2.055	2.197	16.9, 21.0	181.9	2.097	[4N]H2Oax
L = DOTAf
CuL2–(1)			2.058	2.301	10.0	150.0	2.139	[2N,2O]2Nax
CuL2–(2)			2.061	2.241	15.0	157.2	2.121	[3N,O]Nax

^aThe literature data for Cu²⁺-DOTA and Cu²⁺-cyclen are reported for comparison.

^bThe experimental error was ±0.001 for g₀ and ±1 × 10^–4 cm^–1 for A₀.

^cThe experimental error was ±0.002 for g_x and g_y, ±0.001 for g_z, and ±1 × 10^–4 cm^–1 for A_x, A_y, and A_z.

^dCalculated by the equation g_0,calc = (g_x + g_y + g_z)/3 on the basis of anisotropic values.

^eFrom ref (41).

^fFrom ref (52).