Structure of bis(L-alaninato)zinc(II) and single crystal EPR spectra of Cu(II) impurities

DALOSTO; FERREYRA; CALVO; PIRO; CASTELLANO

JOURNAL OF INORGANIC BIOCHEMISTRY

ELSEVIER SCIENCE INC

Año: 1999 vol. 73 p. 151 - 155

0162-0134

The title compound (CHCO2CH3NH2)2Zn(II), abbreviated as Zn(l-alanine)2, crystallizes in the monoclinic space group P21 with a = 8.637(1), b = 5.334(1), c = 9.581(1) Å, β = 90.36(1)°, and Z = 2. The structure was solved employing 1206 independent X-ray reflections with I > 2gs(I) by Patterson and Fourier methods and refined by full-matrix least squares to R1 = 0.031. The Zn(II) ion is fivefold coordinated with two bidentale amino acid ligands and a carboxylate oxygen of another symmetry-related alaninate ion. EPR spectra of copper impurities were measured with the magnetic field in three orthogonal planes of a single crystal sample. The g and hyperfine coupling tensors were evaluated from the spectra. These values are discussed in terms of the structure of Zn(l-alanine)2 and compared with those reported for the quasi-isomorphic compound Cu(l-alanine)2. The distortion of the Zn site when occupied by copper(II) impurities is analyzed.Citado: 14