The objectives are to better understand the electronic structure and behavior of organic molecules and their aggregates that are prototype to health related systems. The work includes the development of unique spectroscopic methods to bring out hitherto unknown structural features. Methods being developed include very high resolution spectroscopy of crystals using lasers and with magnetic and electric fields. The research uses and develops laser techniques for the study of complex systems: In particular novel experiments are proposed using dye lasers and picosecond lasers to explore dynamical properties of excited states in aggregates and non-radiative relaxation pathways in metalloporphyrins. The research also seeks to develop the theory and experimental aspects of resonance light scattering and use coherent resonant quasi-Raman processes to learn details of the structures of prototype organic molecules, and hemeproteins. A major new direction of the research involves direct studies of the chemical dynamics of diatom (O2, CO, NO) interactions with heme in prototype systems as well as hemeproteins. These experiments involve picosecond timescale spectroscopic and kinetic studies having unprecendented precision. Experiments are planned to measure vibrational relaxation times and vibrational energy transfer dynamics in aggregated systems such as isotopically mixed molecular crystals. The vibrational relaxation dynamics of simple diatomic and triatomic ions in aqueous solution will be explored, and used to generate theoretical models for energy transfer. Experiments related to the basis of coherent light generation in molecular four-level systems are planned in order the resonant CARS and CSRS processes can be properly understood, and applied to interesting spectroscopic questions. Metalloporphyrins in paraffins at low temperature will be studied using resonant CARS and CSRS. An experimental approach to picosecond transient Raman spectroscopy is planned, focused initially on FeTPP:C1 and HbX dissociation.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM012592-21
Application #
3268389
Study Section
Biophysics and Biophysical Chemistry A Study Section (BBCA)
Project Start
1977-02-01
Project End
1987-01-31
Budget Start
1985-02-01
Budget End
1986-01-31
Support Year
21
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Type
Schools of Arts and Sciences
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Chuntonov, Lev; Pazos, Ileana M; Ma, Jianqiang et al. (2015) Kinetics of exchange between zero-, one-, and two-hydrogen-bonded states of methyl and ethyl acetate in methanol. J Phys Chem B 119:4512-20
Ghosh, Ayanjeet; Tucker, Matthew J; Gai, Feng (2014) 2D IR spectroscopy of histidine: probing side-chain structure and dynamics via backbone amide vibrations. J Phys Chem B 118:7799-805
Ma, Jianqiang; Pazos, Ileana M; Gai, Feng (2014) Microscopic insights into the protein-stabilizing effect of trimethylamine N-oxide (TMAO). Proc Natl Acad Sci U S A 111:8476-81
Ghosh, Ayanjeet; Wang, Jun; Moroz, Yurii S et al. (2014) 2D IR spectroscopy reveals the role of water in the binding of channel-blocking drugs to the influenza M2 channel. J Chem Phys 140:235105
Pazos, Ileana M; Ghosh, Ayanjeet; Tucker, Matthew J et al. (2014) Ester carbonyl vibration as a sensitive probe of protein local electric field. Angew Chem Int Ed Engl 53:6080-4
Ma, Jianqiang; Komatsu, Hiroaki; Kim, Yung Sam et al. (2013) Intrinsic structural heterogeneity and long-term maturation of amyloid ? peptide fibrils. ACS Chem Neurosci 4:1236-43
Singh, Prabhat K; Kuroda, Daniel G; Hochstrasser, Robin M (2013) An ion's perspective on the molecular motions of nanoconfined water: a two-dimensional infrared spectroscopy study. J Phys Chem B 117:9775-84
Kuroda, Daniel G; Abdo, Mohannad; Chuntonov, Lev et al. (2013) Vibrational dynamics of a non-degenerate ultrafast rotor: the (C12,C13)-oxalate ion. J Chem Phys 139:164514
Kuroda, Daniel G; Bauman, Joseph D; Challa, J Reddy et al. (2013) Snapshot of the equilibrium dynamics of a drug bound to HIV-1 reverse transcriptase. Nat Chem 5:174-81
Chuntonov, Lev; Kuroda, Daniel G; Ghosh, Ayanjeet et al. (2013) Quantum Beats and Coherence Decay in Degenerate States Split by Solvation. J Phys Chem Lett 4:1866-1871

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