Unusual magnetic chain of copper(II) ions in [Cu(pepci)Br]n-[PF6]n[pepci =N-(2-pyridylethyl)pyridine-2-carbaldimine]

Abstract

The complex [Cu(pepci)Br]PF₆[pepci =N-(2-pyridylethyl)pyridine-2-carbaldimine] has been synthesised and characterization by X-ray crystallography shows it to contain cationic mono-µ-bromocopper(II) chains, with two crystallographically independent consecutive cations forming –Cu(pepci)–Br–Cu(pepci)–Br– units which repeat by translation to give the chain structure, and isolated PF₆^– counter ions; the ESR spectrum, showing the forbidden ΔM_s= 2 transition, is indicative of interactions between copper(II) pairs, and the preliminary magnetic susceptibility data indicate a weak antiferromagnetic behaviour.