Synthesis, Characterization and Chromotropic Properties of MnII, CoII, NiII and CuII with Bis(acesulfamato) Bis(3-methylpyridine) Complexes

Abstract

The novel [M(acs)<inf>2</inf>(3-pic)<inf>2</inf>(H<inf>2</inf>O) <inf>2</inf> [M: MnII, CoII, and NiII] and [Cu(acs)<inf>2</inf>(3-pic)<inf>2</inf> complexes (acs: acesulfamate; 3-pic: 3-methylpyridine) have been synthesized and characterized using elemental analyses, magnetic moments, UV-Vis and FT-IR spectra. The thermal behaviour of the complexes was also studied by simultaneous TG, DTG and DTA methods in static air atmosphere. The chromotropic properties of all complexes have been studied using thermal and spectral analysis. While the complexes of CoII and NiII show reversible continuous thermochromism, an irreversible discontinuous thermochromism is observed in the MnII and Cu II) complexes in the solid state. The observed thermochromism in the MnII, CoII and NiII complexes is due to the different ligand field strength associated with the deaquation reaction. The solvatochromic behaviour of the complexes is also studied and all [M(acs) <inf>2</inf>(3-pic)<inf>2</inf>] anhydrous complexes (except MnII) exhibit solvatochromic properties depending on the donor number of the solvent. © 2007 Springer.