| Abstract: | A magnetic and structural characterization of single crystals of the copper derivative of the amino acid -isoleucine, Cu[NH2(CH)2CH2(CH3)2CO2]2, was performed by EPR and X-ray diffraction techniques. The complex crystallizes in the orthorhombic space group Aba2, with a = 11.165(3) Å, b = 11.111(3) Å, c = 25.985(6) Å, and Z = 8. The copper ions occupy sites of point symmetry C2. The position and peak-to-peak linewidth of the single EPR line observed were measured at 9.7 GHz and 293 K in three perpendicular planes of the sample. The gyromagnetic tensor has near axial symmetry around , with a small anisotropy in the perpendicular plane, in agreement with the orthorhombic symmetry indicated by the crystallographic results. The principal values of are g1 = 2.0607(5), g2 = 2.0616(5), and g3 = 2.2619(3), with principal directions parallel to the crystal axes. The observed angular variation of the linewidth suggests a layered arrangement of the copper ions. |
