Table 2. Principal g and copper hyperfine values of the mononuclear Cu^II complexes in the different reaction mixtures heated to 100 °C ^a .

Entry		[CuI] (M)	Heating time		g x ± 0.002	g y ± 0.002	g z ± 0.001	|Ax| (MHz) ± 15	|Ay| (MHz) ± 15	|Az| (MHz) ± 5
1	CuI/DMSO	0.05	10′	I	2.082	2.087	2.405	45	55	385
2	CuI/DMSO/AcOH	0.05	10′	I′	2.081	2.083	2.403	26	25	375
				II	2.080	2.080	2.374	30	26	430
3	CuI/DMSO/AcOH/(1)	0.05	5′	III b	2.070	2.070	2.333	25	25	440
				IV	2.062	2.063	2.286	35	35	510
4	CuI/DMSO/AcOH/(1)	0.05	10′	III b	2.070	2.070	2.333	25	25	440
				IV	2.062	2.063	2.286	35	35	510
5	CuI/DMSO/AcOH/(1)	0.05	1 h	IV	2.063	2.063	2.285	30	30	510
6	CuI/DMSO/AcOH/(1)	0.05	4 h	IV′	2.063	2.063	2.290	30	30	505
				V	2.067	2.067	2.262	35	35	560
7	CuI/DMSO/AcOH/(1)	0.25	10′	IV	2.066	2.066	2.286	35	35	510
				III c	2.072	2.072	2.330	25	25	450
8	CuI/DMSO/AcOH/(1)	0.25	4 h	IV	2.062	2.063	2.285	35	35	510
				III c	2.075	2.072	2.334	25	25	455

^aThe relative contributions of the different species to the experimental spectra are given in the ESI.

^bFor the simulation of the contribution of species III in reaction mixture with starting concentration [CuI] = 0.05 M, the interaction with two ¹⁴N nuclei with a isotropic hyperfine coupling of 40 ± 5 MHz had to be taken into account.

^cThe ¹⁴N hyperfine interaction was not resolved due to the increased linewidth, but was considered in the simulation.