Silver(i) supramolecular complexes generated from isophorone-based ligands: crystal structures and enhanced nonlinear optical properties through metal complexation

Abstract

By self-assembly of (E)-2-(3-(4-(1H-imidazol-1-yl)styryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile (L¹) and (E)-2-(3-(4-(1H-1,2,4-triazol-1-yl)styryl)-5,5-dimethylcyclohex-2-enylidene)malononitrile (L²) with silver(I) salts, eight new complexes, namely AgL¹₂ClO₄ (1), AgL¹₂NO₃ (2), [AgL¹₂NO₃]·C₆H₆ (3), [AgL¹₂OOCCF₃]·C₆H₆ (4), [AgL¹₂PF₆]·C₆H₆ (5), AgL²₂NO₃ (6), [AgL²OOCCF₃]₂ (7) and AgL²₂PF₆ (8), are presented along with an analysis of their structural features. The structures are built up through the combination of coordination bonds, Ag⋯π, Ag⋯F (or O), hydrogen bonding, and π⋯π stacking interactions to generate new supramolecular architectures. We observed the formation of two-dimensional coordination polymers for complex 7. Solvent benzene molecules and anions are dispersed in the supramolecular structure and play a vital role in building the supramolecular structures of the complexes. The nonlinear optical (NLO) properties of the complexes were investigated using the Z-scan technique and complexes 1, 2, 3, 4 and 7 show obviously nonlinear absorption compared with ligands (L¹ and L²).