Structural heterogeneity of Ag I complexes with a flexible 1,2-bis[(imidazol-2-yl)thiomethyl]benzene ligand and issues regarding the phase purity of the bulk material
A series of Ag I coordination compounds with a new ligand, 1,2-bis[(imidazol-2-yl)thiomethyl]benzene, and counterions such as PF 6 -, SbF 6 -, CF 3SO 3 -, BF 4 - and NO 3 - was characterised by powder and single-crystal XRD. Powder XRD revealed the presence of a mixture of crystallographic phases that were further identified by single-crystal XRD. Despite conformational flexibility, 1,2-bis[(imidazol-2-yl)thiomethyl]benzene has a tendency to form N,N-chelated Ag I mononuclear cationic complexes with a linear N-Ag I-N unit. However, T-shaped geometry (N 2O) around the silver ion was also observed, which involved solvent molecules and/or counterions. The formation of a cationic 1D chain with the N,N′-bridging ligand was revealed with the BF 4 - counterion. Coordination compounds that possess different nuclearity were formed with the NO 3 - counterion. In the dinuclear and trinuclear complexes, the ligand showed bischelating behaviour with N-donor atoms that interact with one and S-donor atoms with another metal centre. Furthermore, the crystal structure of the trinuclear complex revealed the presence of two crystallographically independent cationic moieties in the asymmetric unit, which only differ by a single O-donor ligand (NO 3 - vs. H 2O), where both of the moieties possess three different geometries around the constituent silver ions. Argentophilic interactions are present in the majority of the reported structures. Available amine N atoms facilitate hydrogen bond formation and promote the occurrence of solvates. An XRD structural study of a series of Ag I coordination compounds with a new flexible ligand, 1,2-bis[(imidazol-2-yl)thiomethyl]benzene, and counterions such as PF 6 -, SbF 6 -, CF 3SO 3 -, BF 4 - and NO 3 - prepared in MeOH in a 1:1 metal/ligand ratio, reveals vast structural diversity and highlights the difficulties of solid-state characterisation of bulk materials. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.