EPR Spectroscopy Investigation of Cu²⁺ Ions Adsorbed in Tannin-Formaldehyde Resins of Mimosa (Acacia mearnsii) Bark Extracts

Table 1

Spectral parameters obtained by simulation of the room temperature EPR spectra of the resins.

Sample	[mT]			[mT]
Cu-RTF	S1	16.50(5)	2.28(1)	1.20(10)	2.08(1)
	S2	15.00(2)	2.32(1)	1.50(10)	2.05(2)
Cu-RTF-A	S1	16.50(5)	2.28(1)	1.30(10)	2.07(1)
Cu-RTF-AV	S2	14.20(2)	2.33(1)	1.20(10)	2.07(1)
		12.78(5)	2.40(1)	1.26(10)	2.09(2)

Cu-RTF: as-prepared copper-loaded resin; Cu-RTF-A: heated resin and Cu-RTF-AV: heated under vacuum resin. Uncertainties are in parenthesis. S1 and S2 refer to Species 1 and Species 2, respectively. Values are for the ⁶³Cu isotope. The linewidths used in the simulations were 7.0(10) mT for the parallel lines and 3.0(5) mT for the perpendicular lines. ^(a)Taken from [17].