THE INFRARED-SPECTRA OF ETHYLENEDIAMINE COMPLEXES .2. TRIS(ETHYLENEDIAMINE), BIS(ETHYLENEDIAMINE) AND MONO(ETHYLENEDIAMINE) COMPLEXES OF METAL(II) HALIDES

The i.r. spectra of the complexes M(en)3X2 (M = Mn, Fe, Co, Ni, Cu, Zn), trans-Cu(en)2X2, Ni(en)2X2 and M(en)X2 (M = Ni, Cu, Zn; X = Cl, Br, I) have been studied. Assignments are proposed for the tris(ethylenediamine) complexes on the basis of 15N-, N2D4- and C2D4-labelling of en and the effects of metal ion substitution in relation to our earlier study of [M(en)3]SO4 complexes. Assignments for the bis(ethylenediamine) complexes are based on our observations of halogen-sensitivity and earlier studies on metal isotope labelling and ligand deuteration of the halide complexes and a normal coordinate analysis of the [Cu(en)2]2+ species. The spectra of the halide complexes have been extended below 200 cm-1 for the first time. Finally, the spectra of the mono(ethylenediamine) complexes are discussed in relation to their known or probable structures. © 1990.