Applied Chemical Engineering

Effect of temperature on tunneling frequency and dynamic behavior of methyl groups in some organic samples

N. A. Khalefa

Medical Instruments Engineering Techniques Department, College of Technical Engineering, University of Al Maarif, Al Anbar, 31001, Iraq

DOI: https://doi.org/10.59429/ace.v8i3.5661

Keywords: spin lattice; methyl group; tunnel splitting; dipole-dipole driven; nuclear magnetic resonance (NMR)

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Abstract

The Measurements of temperature relaxation (T₁) of methyl groups (CH₃)₃, the tunnel splitting (ut Hz), and energy activation (Eg) of some organic chemistry samples were done in this work. The Measurements were performed at different temperature ranged from 4 – 300 K. It was found that the Eg values for all the compounds ranged from 480-1240 kg/mol and the data was used to measure the magnitude values of the potential energy barriers (V₃) of the (CH₃)₃ in these compounds. The thermal composition mechanism was also investigated and the results indicate the relationship between the hopping rate and the form and height of the levels hindering barriers of collective motion of methyl group protons in samples. In this research, additional calculation for CH₃ tunneling splitting as a result to tunneling frequency was also performed.

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