The focus of our research interests is two-fold:
Developing a molecular-level understanding of the dynamics of chemical reactions occurring in solution, and;
Gaining a deep, detailed insight into the dynamics and
mechanisms of ultrafast (femto- and picosecond) photoinduced processes.
Our primary interest is "real time" investigation of ultrafast excited-state dynamics, bond rupture, and rearrangement of liquid-phase small polyatomic molecules, with most attention currently centered on polyhalogenated alkanes and transition metal complexes. The knowledge of the interplay between the initially populated Franck-Condon region, adiabatic/non-adiabatic excited-state dynamics, energy flow and solute-solvent interactions, is of central importance for achieving control over the photoreaction path. In our research, we use state-of-the-art experimental methods of ultrafast time-resolved spectroscopy, primarily deep-UV-through-near-IR pump/probe and laser pump/x-ray absorption probe.
O’Connor, T.; Panov, M. S.; Mereshchenko, A. S.; Tarnovsky, A. N.; Lorek, R.; Perera, D.; Diederich, G.; Lambright, S.; Moroz, P.; Zamkov M. The Effect of the charge-separating interface on exciton dynamics in photocatalytic colloidal heteronanocrystals. ACS Nano 2012, 6, 8156-8165. [Link]
Mereshchenko, A. S.; Pal, S. K.; Karabaeva, K. E.; El-Khoury, P. Z.; Tarnovsky, A. N. The photochemistry of monochloro complexes of copper(II) in methanol probed by ultrafast transient absorption spectroscopy. J. Phys. Chem. A, 2012, 116, 2791-2799. Femtochemistry: Special issue. [Link]
Zheldakov, I. L. Ryazantsev, M. N. Tarnovsky, A. N. Wavepacket motion via a conical intersection in the photochemistry of aqueous transition-metal dianions. J. Phys. Chem. Lett. 2011, 2, 1540–1545. [Link]
Pal, S. K.; Mereshchenko, A. S.; El-Khoury, P. Z.; Tarnovsky, A. N. Femtosecond photolysis of CH2Br2 in acetonitrile: capturing the bromomethyl radical and bromine-atom charge transfer complex through deep-to-near UV probing. Chem. Phys. Lett. 2011, 507, 69-73. [Link]
Khon. E.; Mereshchenko, A.; Tarnovsky, A. N.; Acharya, K.; Klinkova, A.; Hewa-Kasakarage, N. N.; Nemitz, I.; Zamkov M. Suppression of the plasmon resonance in Au/CdS colloidal nanocomposites. Nano Lett., 2011, 11, 1792–1799. [Link]