Title :

Medium Matters: Dynamics of Molecules in a Confined Space

Abstract :

From time immemorial it is well known that curtailment of freedom often leads to changes in the behaviour of living beings. Similar restriction of freedom leads to selectivity in the chemical behaviour of molecules embedded in biological systems. Extending these well-known behaviours, supramolecular chemists have established that even small molecules upon confinement in synthetic hosts exhibit behaviour distinctly different from the ones in a bulk isotropic solution.

In this lecture the role a “Medium” in bringing about changes in the well-established behaviour of excited molecules would be illustrated with select examples. Results of steady state and ultrafast experiments will be presented that highlight how the confinement alters the excited state dynamics of molecules such as stilbenes, azobenzenes, anthracene, dibenzyl ketones etc. Another reaction to be discussed concerns with electron transfer and spin transfer that play a fundamental role in a number of biological events including photosynthesis. Examples and ultrafast dynamics of electron and spin transfer between a confined and a free molecule would be presented.

The main message of the talk is that molecules like humans behave differently when confined within synthetic cages.

Selected references

[1] V. Ramamurthy, S. Jockusch and M. Porel, Langmuir, 2015, 31, 5554-5570

[2] V. Ramamurthy, Acc. Chem. Res. 2015, 48, 2904-2917.

[3] A. Mohan Raj, M. Porel, P. Mukherjee, X. Ma, R. Choudhury, E. Galoppini, P. Sen and V. Ramamurthy, J. Phys. Chem. C, 2017, 121, 20205−20216.

[4] C-H. Chuang, M. Porel, R. Choudhury, C. Burda and V. Ramamurthy, J. Phys. Chem. B, 2018, 122, 328−337.

[5] C. J. Otolski, A. Mohan Raj, V. Ramamurthy and C.G. Elles, J. Phys. Chem. Lett. 2019, 10, 121−127