S. Beukeleer, H. Desseyn, S. Perlepes
Jun 16, 1995
Citations
0
Influential Citations
5
Citations
Journal
Thermochimica Acta
Abstract
Abstract In alkaline medium, malonamide forms anionic planar complexes [ML 2 ] 2− · x H 2 O where M is Ni or Cu. Thermograms and vibrational spectra clearly indicate that three different nickel anion complexes could be isolated, with x being respectively 2, 1 and 0. Only the monohydrate has been observed for the copper anionic compound. Malonamide also forms neutral trans -octahedral M(LH 2 ) 2 X 2 complexes (where M is Mn, Fe, Co, Ni, Cu, Zn; X is Cl, Br, I; LH 2 is CH 2 (CONH 2 ) 2 and polymeric [Cu(LH 2 )X 2 ] n compounds (X is Cl or Br). The neutral 1 2 complexes all decompose, forming free ligand and MX 2 by an endothermic reaction, except for Fe(II) where an exothermic reaction occurs at relatively low temperatures. The thermal breakdown of Cu(LH 2 ) 2 Cl 2 and [Cu(LH 2 )Cl 2 ] n results in new polymeric structures, exhibiting bridging chlorines. The structures proposed for these compounds are supported by infrared spectra. The thermal stability of the M(LH 2 ) 2 X 2 complexes can be related to the metal-ligand bond strength and obeys the crystal field stabilization theory.