Acetonitrile-induced structure fine-tuning of a trinuclear zinc complex showing multistimuli responsive luminescence

Abstract

A novel trinuclear Zn(II) complex, [Zn₃L₂(OAc)₄]·1.5CH₃CN (1, HL = 2-benzothiazolyl-6-phenyliminomethylphenol), with three coordination geometries for Zn(II) ions exhibits mechanochromism and acidochromism with multicolor switching and high contrast beyond 100 nm. Complex 1 lost the solvent molecules accompanied by a phase transformation during the heating process. The PXRD pattern of the sample heated at 200 °C (1-200heated) is consistent with that of complex 2 without solvent molecules. The crystal structure analyses of 1 and 2 show that the presence or absence of acetonitrile molecules makes the intermolecular interactions and packing fine-tuned. The presence of acetonitrile molecules is conducive to more obvious mechanochromic luminescence (MCL) properties. Furthermore, 1 is also made into a test paper for the detection of mechanical and HCl/NH₃ vapor stimuli.