Executive Summary : | Crystal adaptronics is a fast progressing field of study involving the applications of the effects of external stimuli over the solid crystalline molecular materials especially single crystals. Dynamic crystals exhibit various motions such as bending, twisting, curling, hopping, crawling, cracking, explosion, etc. in the presence of external stimuli such as light, heat, humidity, organic solvent vapors, mechanical force, etc. These crystals are useful sources of harvesting one form of energy to another such as light, heat, stress to mechanical, kinetic energy, electrochemical energy and work. Mechanically flexible and stimuli responsive organic crystals have gained importance in the recent years owing to their light weight, easy synthesis, flexibility, crystalline nature, and application in devices. Single crystals of organic molecules with mechanical flexibility are useful in the biomedical applications including pharmaceuticals, photoluminescence, biosensors, etc. Single crystals have advantages over polymers, gels, ionic liquids in terms of high durability, processability, cost-effectivity, and performance. Overall, the understanding of the structure-property relationship in these organic crystals is important in the design of smart functional materials. Molecular single crystals have work density < 2000 kg m-3, high elastic modulus, generate forces between 10-4- 0.1 N which are in the range of electroactive polymers, MEMS, gels, etc used for actuator purposes with faster response time. In the design of mechanically flexible organic/inorganic crystals, supramolecular interactions such as hydrogen bonding, van der Waals interactions, halogen- halogen bonding, pi-pi interactions, alkyl interactions play the key role. Apart from that, crystallization conditions and choice of solvents, temperature, etc. play a secondary role whose applications in orthopaedic biomedical devices is hardly studied so far. During the project, we expect to understand the fundamental mechanisms in terms of mechanistic studies, crystal growth mechanisms, phase transitions, polymorphic transformations, and energy conversions and use these materials for flexible device applications. The synthesis of the materials would be done using crystallization methods, organic synthesis, mechanochemistry and, hydrothermal methods. We would also explore the actuating properties, response time, mechanical work and assisted locomotion in the devices constructed with the help of these flexible crystals. This project is important both from the fundamental and application aspects since we would focus on the complete study ranging from the design, synthesis to the fabrication in orthopedic biomedical devices. |