Chemistry Faculty:
Nigel G. Adams, Ph.D.
Distinguished Research Professor
Phone: 706-542-3722
E-mail: adams@chem.uga.edu
Biographical Information
Ph.D, 1966; DSc, 1978, University of Birmingham, England
Research Interests
Whether reactions proceed, and the speed at which they occur, is central to chemistry. We study the kinetics of reactions between ions, electrons and neutral molecules in low-pressure gas, which are little influenced by solvent effects and thus reaction mechanisms can be investigated. As well as fundamental significance, the reactions are important in planetary atmospheres (including our environment), interstellar gas clouds, isc, where stars are forming, comets, combustion flames, plasmas used to etch semiconductor chips, etc. Reactions include proton transfer, ion-molecule association and electron-ion recombination. For these studies, we have developed flow tube apparatuses (selected ion flow tubes, SIFT, and flowing afterglows) coupled with mass spectrometers, electrostatic probes and a series of spectroscopic techniques (Vacuum Ultra-violet, visible, infra-red emission and absorption spectroscopy, Laser Induced Fluorescence, etc.) covering the wavelength range 100 nm to 10 microns.
Some recent results are: (i) The influence of quantum tunneling on the products of the recombination of N2H+ ions with electrons. (ii) Recombination studies of linear and cyclic isomers of C3H3+ and the temperature dependence of their production in ion-neutral reactions; the first time this has been achieved. The neutral products of such reactions are so important and understudied that, in NSF funded research, we are developing techniques to quantitatively identify these for a variety of chemical reactions, to provide kinetic data and enable mechanisms to be understood. (iii) Laboratory searches for gas phase routes to the production of pre-life molecules in isc.
Publications
Flowing Afterglow Studies of the Temperature Dependencies for Dissociative Recombination of O2+, CH5+, C2H5+ and C6H7+ with Electrons. J. L. McLain; V. Poterya; C. D. Molek; N. G. Adams; L. M. Babcock. J. Phys. Chem. A 108, 6704-8 (2004).
Electron-Molecular Ion Recombination: Product Excitation and Fragmentation. N. G. Adams; V. Poterya; L. M. Babcock Mass Spectrom. Rev. 2005, in press.
Molecular Ion Recombination in Trapped and Flowing Plasmas: Methods, Recent Results, New Goals, Open Questions. N. G. Adams; L. M. Babcock. J. Phys. Conf. Ser. 4, 38-49 (2005).
C3H3+ Isomers: Temperature Dependencies of their Production in the H3+ Reaction with Allene and their Loss by Dissociative Recombination with Electrons. J. L. McLain; V. Poterya; D. M. Jackson; N. G. Adams; L. M. Babcock. J. Phys. Chem. A 109, 5119-23 (2005).
Mechanism of the Electron-Ion Recombination of HCO+/DCO+ and N2H+/ N2D+ Ions: Temperature Dependence and Isotope Effect. V. Poterya; J. L. McLain; L. M. Babcock; N. G. Adams. J. Phys. Chem. A 109, 7181-6 (2005).
A Selected Ion Flow Tube Study of the Reactions of Various Nitrogen Containing Ions with Formic Acid, Acetic Acid and Methyl Formate. D. M. Jackson; N. J. Stibrich; J. L. McLain; L. D. Fondren; N. G. Adams; L. M. Babcock. Int. J. Mass Spectrom. (2005) available on line.