STRUCTURE AND SPECTROSCOPIC PROPERTIES OF DI(3-AMINOPROPYL)AMINE-N,N',N''][IMINODIACETATO-N, O, O']CHROMIUM(III) PERCHLORATE

The mixed-ligand complex [Cr(dpt)(ida)]ClO4.2H2O (dpt = di(3-aminoprop yl)amine, H-2ida = iminodiacetic acid) adopts a structure in which the ligands are tridentate and coordinate facially, with the imino nitrog en trans to the dpt secondary amine. Thus the preference of iminodiace tate for facial coordination prevails over the preference of di(3-amin opropyl)amine for meridional coordination. The crystal structure of th e title complex has been determined: space group Pbca; a = 17.609(2), b = 14.762(2), c = 14.423(2) angstrom, Z = 2. An analysis of the 4A2g --> {2E(g), 2T1g} electronic spectrum shows the iminodiacetate carboxy late groups to be moderately strong sigma- and pi-donors.