Dynamic NMR of Intramolecular Exchange Processes in EDTA Complexes of Sc3+, Y3+, and La3

This article describes an advanced physical chemistry lab experiment on dynamic NMR (DNMR) of intramolecular exchange processes in EDTA (the disodium salt of ethylenediaminetetraacetic acid) complexes of Sc3+, Y3+, and La3+. This lab experiment is intended for chemistry and biochemistry undergraduates, who have finished or are in the process of completing the physical chemistry course sequence. Three six-hour laboratory sessions, covering the synthesis of the EDTA complexes, the NMR experiment, and the calculation of the DNMR lineshapes are assigned for this lab experiment. This lab experiment is an integration of analytical chemistry, physical chemistry, instrumental analysis, NMR spectroscopy, and computational skills. It provides a challenging hands-on experience for students to use this comprehensive technique to study chemical exchanges. Rate constants at different temperatures and activation energies of the nitrogen inversion processes for these EDTA complexes are obtained in this lab experiment.