Theoretical Physics Colloquium

Electron Transfer Processes in Organic Matter

by Prof. Ravi Venkatramani (TIFR, Mumbai)

Tuesday, August 6, 2019 from to (Asia/Kolkata)
at AG 69
A major effort in our research group is the theoretical/computational description of electronic charge flow through organic molecules under diverse conditions that occur in nature and experimental setups. After reviewing the field and our methods, I will present two ideas that have emerged through our efforts in last few years. 

In conventional electrical and electronics engineering, solderless breadboard scaffolds are routinely used for quickly creating/testing a range of electrical circuits of varied complexity. I will discuss how the idea of breadboard circuits can be realized within a molecular junction possessing quantum interference effects and significant thermal fluctuations. [1] 

I will report the discovery of a new optical charge transfer (CT) band in proteins.[2] The CT band is specific to proteins rich in charged amino acids and can span the UV-Vis range of the electromagnetic spectrum between 250- 800 nm. I will show that this band arises due to the intrinsic electronic properties of charged amino acids and is highly sensitive to their interactions imposed by protein folds.

Our conclusions are supported by experimental data from collaborators and I will highlight challenges and future directions in both projects.

[1] Conductance in a Bis-Terpyridine Based Single Molecular Breadboard Circuit, Seth. et. al.  Chemical Science, 8, 1576 - 1591 

[2]"Near UV-Visible Electronic Absorption Originating from Charged Amino Acids in a Monomeric Protein" Prasad et. al. Chemical Science, 8, 5416