Robert J. LeRoy

Robert J. LeRoy
Born (1943-09-30) September 30, 1943
Ottawa, Ontario
 Canada
Known for LeRoy radius
LeRoy-Bernstein theory
Sequential Rounding and Refitting
Website
Department of Chemistry, LeRoy

Dr. Robert J. LeRoy (born September 30, 1943 in Ottawa) is one of Canada’s leading chemists and is currently a University Professor at the University of Waterloo.

LeRoy received the BSc and MSc degrees from University of Toronto in 1965 and 1967, respectively, and a PhD degree from University of Wisconsin–Madison in 1971.

LeRoy is renowned for two major achievements in the field of chemistry: the development of the near-dissociation theory, alongside R. B. Bernstein, and the derivation of the LeRoy Radius. LeRoy is also the author of many computer programs that aid in collecting information from experiments. Many of his works are used by schools and labs throughout the world and have contributed to the progress of science.

He is a graduate from the University of Toronto. During his stay there, he began working with theoretical and computational chemical physics, which is what he would deal with for the rest of his career.

In his research, Dr LeRoy involves using quantum mechanical theory to understand and explain how properties of molecular systems are the results of forces of interaction by quantitatively determining those forces from measurements of various properties.

In almost any area of science today, the experimental work runs parallel to the theoretical work and there is constant interplay between the two areas. In Canada there are several theorists whose research teams examine the forces between atoms and molecules to increase our understanding of physical and chemical properties. One such individual is Dr. Robert LeRoy, currently working in theoretical chemical physics at the University of Waterloo. Dr. LeRoy’s interest is intermolecular forces. He uses quantum mechanics and computer models to define and analyze the basic forces between atoms and molecules. Early in his career, Dr. LeRoy developed a technique for mathematically defining a radius of a small molecule, now known as the LeRoy radius. This established a boundary.Within the boundary, intramolecular bonding is important, and beyond the boundary, intermolecular forces predominate. In his work, the study of atomic and molecular spectra (called spectroscopy) plays a crucial role. Measurements from spectroscopy help theoreticians develop better models and theories for explaining molecular structure.Computer programs that Dr. LeRoy has developed for the purpose of converting experimental evidence to information on forces, shape, and structure are free, and are now routinely used around the world. It is important not to assume that forces and structures are well established. Our knowledge of bonding and structure becomes more and more scanty and unreliable for larger structures. A huge amount of research remains to be done if we are ever to be able to describe bonding and structure very accurately for even microscopic amounts of complex substances. Dr. LeRoy states “... except for the simplest systems, our knowledge of (interactions between molecules) is fairly primitive... .” A classic example is our understanding of the structure and activity of proteins—the stuff of life.We know the composition of many proteins quite precisely and the structure can be experimentally determined, but the structure of these large molecules depends on how bonding folds and shapes the chains and branches. How a protein behaves and what it does depends specifically on its precise shape and structure, and that is something scientists often state is “not well understood.”

His work on the Morse/Long-range potential was referred to as a "landmark in diatomic spectral analysis" in.[1] In the landmark work, the C3 value for atomic lithium was determined to a higher-precision than any atom's previously measured oscillator strength, by an order of magnitude. This lithium oscillator strength is related to the radiative lifetime of atomic lithium and is used as a benchmark for atomic clocks and measurements of fundamental constants.[2]

References

  1. Tang, Li-Yan; Z-C. Yan, T-Y Shi, J. Mitroy; Shi, Ting-Yun; Mitroy, J. (30 November 2011). "Third-order perturbation theory for van der Waals interaction coefficients". Physical Review A. 84 (5): 052502. doi:10.1103/PhysRevA.84.052502.
  2. Mitroy, Jim; Mariana S. Safranova, Charles W. Clark (4 October 2010). "Theory and applications of atomic and ionic polarizabilities". Journal of Physics B: Atomic, Molecular and Optical Physics. 43: 202001. doi:10.1088/0953-4075/43/20/202001.
This article is issued from Wikipedia - version of the 3/20/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.