Inderdip Shere
I n the field of molecular simulation, my research is mainly focused on understanding macroscopic behavior from the molecular perspective. Using Monte Carlo and Molecular dynamic techniques, algorithms are developed to mimic multi-length and time molecular events occurring in silica as a model system.
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The role of functionality, concentration, and solvent reactivity in governing the silica morphology was established. Also, force fields were developed for the coarse-grained silica bead model, and nano-particle self-assembly and the percolating structure were observed due to physical association between beads.
Reaction Algorithm
Fascinating materials are synthesized using silica polymerization, such as zeolite and aerogels. Synthesis parameters are nudge by trial and error to obtain desire products due to the lack of fundamental understanding of the silica system.
We developed algorithms to mimic the molecular behavior of silica species using the Monte Carlo technique, the results of which agree excellently with experimental observation. We identified four stages of the polymerization based on molecular reactions and the shape of the silica aggregate.
Porosity Development
Silica polymerization is widely used to synthesize porous catalysts. Generally, a structure-directing agent or a template is used to control the porosity of the materials. In the absence of such agents, the mechanism of pore formation is not known.
We use molecular simulation to probe pore development by formulating an algorithm to estimate the porosity of irregular non-periodic particles. We observed different tow routes of pore formation in the silica system, which can be controlled by the concentration of precursor and type of solvent used. Using the concentration, time porosity phase diagram, one can obtain the product of any desired porosity.
Reaction Mechanism
Impressive materials are obtained by the arrangement of the ring in a different fashion. In the absence of any structure directing agent, the self-assembly of these rings is erratic, and behavior can not be predicted.
Using the Monte Carlo based algorithm to mimic molecular behavior, we studied the formation and arrangement of the two most widely encountered rings (four members and six-member rings). We calculated the probability of a ring to stay in the system before it breaks and rearranges. Using these probabilities, we perform extensive rate estimation and obtain a model fo different steps leading to the final ring arrangement.
The knowledge to tweak the arrangement of rings by controlling concentration and time is extremely useful in designing tailor-made materials.
Coarse-grained Model
Nanoparticles are extensively used in drug delivery. Studying nanoparticle formation using simulation is extremely time-consuming due to the large system size.
To study molecular-level interaction of silica species, we develope a coarse model where entire silica is treated as one entity. We iteratively refined the potential of the interaction of coarse particles to match actual silica species. Using developed forcefield, we studied the formation of large nanoparticle and also the percolating structure.
The coarse grain model can simulate a massive system in a considerable amount of computational time.
If you want to understand the molecular behavior then sit on one of them and live in the journey which tiny species make.
-My Guide
When you spend more of all of these, Time, Efforts and Money, on anything you automatically inclined to love that thing.
- My Guide
