Photochemical Reactions of Hydrogen-bonded Coordination Polymers

Crystallization is a kinetic phenomenon and the experimental conditions like solvents, concentration, pH, temperature and time have greater influence on the nature of products in the synthesis of coordination network structures. During crystallization, the solvents and ligands bind to the metal ions reversibly and hence, the least soluble polymer will crystallize first, independent of the metal-ligand ratio used in the crystallization. The kinetic products quite often contain solvents bonded to the metal ions. The removal of these coordinated solvents is likely to transform the kinetically formed coordination polymers (CPs) into thermodynamically stable products. In these structural conversions, supramolecular interactions play a major role. Such structural transformations as well as [2+2] cycloaddition reactions have been demonstrated in many coordination polymeric network structures aided by the directional hydrogen bonding interactions. A number of structural transformations involving the loss of solvent molecules and use of photodimerization reactions in the solid state will be presented in this talk.

IYCr outcome in SE Asia

Crystallography has been extensively practiced in a number of Asian countries such as India, China, Japan, S. Korea, Taiwan, Australia, New Zealand and Singapore, and to a lesser extent in Malaysia and Thailand for decades, but not in many parts of South East Asia. The International Year of Crystallography (IYCr 2014) provided an opportunity to reach out some of these countries to initiate or intensify the crystallographic activities in terms of workshops, conferences, crystal growing competition, etc. As a part of this initiative, the IUCr with the help of the Asian Crystallographic Association contacted various academicians and researchers in Malaysia, Thailand, Indonesia and Fiji to increase the awareness of the science of crystallography through various activities, to promote education and research in crystallography and to inspire young people through hand-on demonstration in school, among the activities planned in 2014. The speaker will collate the details of these activities and present in his talk. He will also discuss details of the Crystal Growing Challenge in Singapore among the other activities planned to celebrate IYCr 2014 in Singapore.