Speaker: Atandrita Bhattacharyya
Topic: Conical Intersections and their Role in Initiating Visual Excitation
Research Supervisor: Prof. Vivek Tiwari
Date & Time: Thursday, 17 November 2022 at 4:00 PM
Venue: AG02/03, Chemical Sciences Building
Born-Oppenheimer approximation is central to chemistry although its breakdown underpins vital ultrafast phenomenon such as rapid internal conversion between excite electronic states in photosynthesis and initiating vision. Since the discovery of the presence of geometric isomerism in the very first step of vision, scientific community were astounded merely by the rapid nature of this internal conversion and what physics might lead rapid internal conversion between electronic states on such timescales.
In my presentation, I will first talk about conical intersections, which exemplify breakdown of Born-Oppenheimer approximations to lead to efficient electronic funnels between adiabatic potentials. Then I will address how conical intersections play a critical role in the photo-isomerization of retinal, a molecule present in rod cells, eventually leading to visual sensation in our brains.
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