First principles study of role of nuclear quantum effects on properties of hiv cancer inhibitor ellipticine in protic solvents and descriptors for predicting efficient dye sensitized semiconductor photocatalysts for hydrogen evolution reaction

Abstract

The thesis is divided into two parts In the first part of the thesis Chapter 3 we have studied the effect of the quantum natureof the nuclei on the structural dynamical and electronic properties of ellipticine a plausible anti HIV cancer drug solvated in water In Chapter 4 we have extended the study to two more protic solvents namely methanol and ethylene glycol and investigatedthe role of nuclear quantum effects NQEs on the solvent solute hydrogen bond H bond and how these affect the H bonding network of the solvent Further we have also discussed how the structural fluctuations induced by NQEs strongly affect the it is to incorporate NQEs in the simulations of H bonded systems even when we are interested in the optical properties of such H bonded systems To achieve this we have used the state of the art path integral molecular dynamics simulations coupled with a recently proposed coloured noise thermostat based on the generalized Langevinequations In the second part Chapter 5 using density functional theory based calculations we have proposed noveldescriptors that can be used to screen materials for the design of more efficient dye sensitized semiconductor photocatalyst forphotocatalytic hydrogen evolution reaction The thesis is divided into six chapters In Chapter 1 we have discussed the importance of nuclear quantum effects and explained how path integral molecular dynamics PIMD simulations could incorporate nuclear quantum effects We have also summarized the challenges of performing a straight forward PIMD simulation and discussed the recent developments of the computational techniques that can overcome some of these challenges Moreover we have also motivated the importance of photocatalytic water splitting in the context ofthe present day energy challenges Further the remaining chapters of the thesis have also been summarized The computational techniques which are used in the thesis are discussed in Chap newline newline