Syntheses, Structure, and Photoluminescence of Three Ion-Pair Compounds Based on [M(mnt)2]2− Building Blocks

Abstract

Three ion-pair complexes, [RhB][M(mnt)2] (RhB+ = 9-(2-carboxyphenyl)-3,6-bis(diethylamino)xanthylium; mnt2− = maleonitriledithiolate; M = Ni (1), Zn (2), Cu (3)) have been synthesized and characterized. The crystal of 1 crystallizes in the monoclinic space group P21/c, the NiS4 core in the [Ni(mnt)2]2− anion exhibit perfect planar geometry. The adjacent anions form a column via lateral-to-lateral S…S interactions along (0 1 1) plane, and the neighboring cations align in a manner of parallel arrangement, also forming cations columns. The weak van de Waals forces as well as Coulomb attractions connect the adjacent anions and cations columns into three-dimensional molecular solid. UV-Vis spectrum studies disclosed that complexes 1–3 show similar absorption band in the 200–330 nm regions and different absorption band positions as well as intensity in the 350–380 nm regions. Photoluminescence investigations reveal that complexes 1–3 display strong main emission spectra peaks at 582, 576, and 579 nm, respectively.