title: Ligand chain length conveys thermochromism.
abstract: Thermochromic properties of a series of non-ionic copper compounds have been reported. Herein, we demonstrate that Cu(II) ion with straight-chain primary amine (A) and alpha-linolenic (fatty acid, AL) co-jointly exhibit thermochromic properties. In the current case, we determined that thermochromism becomes ligand chain length-dependent and at least one of the ligands (A or AL) must be long chain. Thermochromism is attributed to a balanced competition between the fatty acids and amines for the copper(II) centre. The structure-property relationship of the non-ionic copper compounds Cu(AL)2(A)2 has been substantiated by various physical measurements along with detailed theoretical studies based on time-dependent density functional theory. It is presumed from our results that the compound would be a useful material for temperature-sensor applications.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India. tpal@chem.iitkgp.ernet.in.
authors.forename: Mainak
authors.initials: M
authors.lastname: Ganguly
authors.forename: Sudipa
authors.initials: S
authors.lastname: Panigrahi
authors.forename: K R S
authors.initials: KR
authors.lastname: Chandrakumar
authors.forename: Anup Kumar
authors.initials: AK
authors.lastname: Sasmal
authors.forename: Anjali
authors.initials: A
authors.lastname: Pal
authors.forename: Tarasankar
authors.initials: T
authors.lastname: Pal