NMR Spectrometry Across the Chemistry and Physics Curriculum

Westmont College, Santa Barbara CA

Investigators

Abstract

Chemistry (12) NMR has revolutionized the modern study of chemical structure and dynamics and all chemistry students need to understand and experience its manifold capabilities. Therefore, a primary educational objective is to increase and diversify the student's exposure to state-of-the-art NMR so they may discover and apply its versatility to challenging problems they will encounter in their professional workplace. The timely and excellent article of Davis and Moore [Journal of Chemical Education, 1999, and the National Science Foundation Division of Undergraduate Education, Award #9751056] is serving as a model for curricular changes and, after modifying some of their experiments and adapting results from our own research and published sources (mainly the Journal of Chemical Education), this model is being implemented. A 300 MHz FTNMR spectrometer is being used to introduce students to NMR techniques as freshmen and then to give them progressively more sophisticated experiences as they proceed through advanced courses and undergraduate research. NMR is serving as a central theme in the chemistry/ biochemistry (14 experiments in 9 courses) and physics (3 experiments in 2 courses) programs. Students are learning about chemical shifts, spin-spin splitting patterns, quantitation using integrated peak intensities, and simple decoupling in their freshman and introduction to organic chemistry courses. NMR characterization of student-synthesized compounds is now routine. In advanced organic chemistry, students are progressing to 2-D COSY and HETCOR techniques. Extension of NMR to solid state and inorganic applications are part of the analytical chemistry course. A metabolic reaction is monitored by NMR in the biochemistry course. The thermodynamics of a keto-enol equilibrium, a gas-phase isotope exchange study, and the spin-saturation technique as an introduction to the kinetics of molecular internal rotation, are investigated with NMR in the physical chemistry laboratory. In physics, students examine the free induction decay of nuclei in an external field, Knight shifts, and the coupling of nuclear magnetic moments with their local environments.