[Hybrid/Webinar] Diffusion, Solvation and Dynamical Heterogeneity in Deep Eutectic Solvents

by Dr Harish Srinivasan (Solid State Physics Division, Bhabha Atomic Research Centre )

Monday 2 May 2022, 14:30 → 15:30 Europe/Berlin

PH HS 3 (Physics Department)

=== Following seminar will be given by Webinar. Audience will still gather at the lecture hall 3.  Small coffee and cookies will be available before the seminar, so join us.  ===

Deep eutectic solvents (DESs) have become ubiquitous in a variety of industrial and pharmaceutical applications since their discovery. However, the fundamental understanding of their physicochemical properties and their emergence from the microscopic features is still being explored fervently. Particularly, the knowledge of transport mechanisms in DESs is essential to tune their properties, which shall aid in expanding the territory of their applications. In this seminar, we will present our investigations carried out on acetamide and lithium perchlorate based DES using neutron scattering and classical molecular dynamics (MD) simulations. The dynamics of acetamide in these solvents comprise localised and jump diffusion processes. The large viscosity and poor conductivity in DESs could be correlated to the slow jump-diffusion of acetamide owing to the extensive hydrogen bond interaction with the ionic species. In particular, the formation of long-lived hydrogen bond complexes are found in these DESs and they're also found to dictate the nature of lithium-ion transport. The dynamics of these systems are rife with dynamical heterogeneities strongly governed by the relaxation dynamics of hydrogen bonding networks. We have also studied and characterized the effect of water on the dynamical landscape of these DESs with key insights into water's ability to tune the transport properties of the solvents.