Mechanochemical synthesis of transition metal co-crystals

This thesis describes the synthesis and characterisation of a number of metal halide complexes, and the subsequent mechanochemical synthesis of co-crystals involving these complexes. Chapter one introduces supramolecular chemistry, with a focus on non-covalent interactions (NCIs) and crystal engineering. It then introduces mechanochemistry, a key synthesis method used throughout this project, as well as powder X-ray diffraction, an analysis technique used extensively in the characterisation of the mechanochemical products. Chapter two discusses system design, as well as difficulties preventing the use of some typical analysis techniques, before detailing the synthesis of a series of MX2(L)2 complexes with monodentate ligands [M = Cu(II), Co(II), Mn(II); X = Cl, Br; L = nicotinamide (nic), isonicotinamide (iso), nicotinic acid (niacin, nia)]. The mechanochemical synthesis of co-crystals involving these MX2(L)2 complexes and a coformer (1,4-diiodotetrafluorobenzene (1,4-tfib) or terephthalamide) is then described, and evidence of formation analysed using powder X-ray diffraction, IR, and low frequency Raman spectroscopy. Chapter three describes the system design and subsequent synthesis of a series of MX2(L)n complexes [M = Co(II), Pd(II); X = Cl, Br; L = 2,9-dimethyl-1,10-phenanthroline (neocuproine, 2,9-mphen), 4,7-dimethyl-1,10-phenanthroline (4,7-mphen), 4,4’-dimethyl-2,2’-bipyridine (4,4-mbpy), 2,2’-bipyridine-4,4’-dicarboxylic acid (4,4-cbpy), 2,2’-bipyridine-6,6’-dicarboxylic acid (6,6-cbpy); n = 1, 2]. The crystal structures of some of these complexes are described. The mechanochemical synthesis of co-crystals involving these MX2(L)n complexes and a coformer (1,4-tfib, terephthalamide) is then described, and evidence of formation analysed using powder X-ray diffraction and IR spectroscopy