Spectroscopy of Transition State Dynamics (1988-1991) 

The laser excitation of a reaction complex formed by colliding reactants (e.g. Na + H2) provides unique insight into the potential energy surfaces for chemical reaction in the region of the transition state between the reactant and product valleys. The probe laser is used for state selective detection of reactants. The theory of spectral line shapes is used to interpret the results. 

State-to- State Photochemistry (1988-1991) 

Nascent rotational and vibrational quantum state distribution of laser induced reactive collisions is determined using laser pump-probe technique. 

Laser Spectroscopy and Photodynamics (1991-1993) 

Excitation of atomic or molecular fluorescence using one or more tunable lasers is of particular interesting studies of atomic interactions and potential energy curves, obtained from spectroscopic data including accurate dissociation energies, long range interactions, spin changing energy transfer collisions (predissociation phenomena) in metal rare gas systems. Semi-classical theory is used to determine the predissociation life times. 

Electronic Structure Calculations (1991-1993) 

The main interest is to perform high level ab initio calculations of ground, excited valence and Rydberg states of metal-rare-gas potential energy curves to compare with a wealth of spectroscopic information already available and being accumulated. There is also an interest in ab initio calculations of metal-hydrogen potential energy surfaces to understand the experiments in part 1,2 and 3. and to develop simple analytical model potential functions to describe the metal-rare-gas van der Waals bonding in different electronic states of Al, Mg, Zn, Cd and Hg. 

Photodetachment of H-  (summer 1995) 

With vacuum UV laser to study state-to-state detachment of negative H- with high photon flux VUV laser beam (100-200nm), and resolve the detached electron energies and determine the final states of the neutralized H atom and match spectral features. Participated in running the lasers. (Los Alamos National Laboratory) 

Study of the Photochemistry of Metal CVD (Photochemical Laser Deposition) precursors in cluster environment: Oak Ridge National Laboratory, (Summer 1996, 1997) 
The study involves using pico-second lasers in combination with mass spectrometry to ionize and characterize novel clusters of organometallic compounds and to investigate subsequent metal-ion chemistry with a variety of simple molecules. 

CURRENT RESEARCH:

Spectroscopy of Transition State Dynamics
(1998-present)

The Department of Physics operates a modern state-of-the-art laser laboratory in the new IRC (Interdisciplinary Research Center) building. The laser lab has two 20 Hz pulsed YAG laser (SURLITE) and two YAG pumped tunable dye lasers (ND6000) with a frequency doubling and tracking option. The research in this lab is funded by the National Science Foundation (NSF) CAREER program. The research being conducted in this lab includes the study of laser induced chemical reactions within molecules, and laser induced energy transfer collisions between atoms and molecules. We are currently studying laser induced chemical reaction dynamics of LiH2, LiCH4 ZnH2 and ZnCH4 complexes in gas phase, and quenching pf excited states of Li by several alkane and alkene hydrocarbons.

Nanoclusters and nanoalloys(2004-)

The current proposed research activities, which make use of the new RTOF-MS and a picosecond laser are the study of the synthesis structure and properties of metal-containing nanoclusters, study of metal-ion chemistry within clusters; and fabrication of nanoscale metallic clusters in different concentration ranges.

CURRENT COLLABORATIONS:

Laboratory of Theoretical Chemistry Facultes de St-Jerome 13397 MARSEILLE

2000-present

Theoretical and Experimental study of Li-H₂, Li-N₂ and Li-CH₄ Collisions.

Dr. Tang & Dr Burbach (NCA&T), Dr. Atalay Wondim (AAU: Ethiopia), NCState University

Dr. Andy Nyblade: PENN STATE, University of the Witwatersrand (South Africa)

Geophysics and Seismic data analysis

Submitted an NSF International Proposal:

“AfricaArray: Imaging the African Superplume, building African partnerships and enhancing diversity in the geosciences.” Requested amount $2.5 Million