Abstract
2H N.M.R. spectra from polycrystalline powders of methyl parathione (MP) and parathione (P) deuterated at the methyl position were studied between 120 and 304 K. To interpret the spectra we used a primarily qualitative rationale, aided by lineshape simulations based on various models for molecular structure and dynamics.We find that all the methyl groups spin rapidly about their internal symmetry axis. Onset of discrete jumps executed by the methyl groups is observed to occur at 275 K with MP-d6 and at 160 K with P-d6 . The former process is interpreted in terms of methyl groups exchanging with the lone pair of the oxygen, whereas the latter reflects predominantly isomerization about the 0-CH2 bond. The temperature-dependence of the2H N.M.R. spectra is interpreted to reflect geometric alterations and a differential in the flexibility of the two methyl groups of a given molecule.
Original language | English |
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Pages (from-to) | 1129-1143 |
Number of pages | 15 |
Journal | Molecular Physics |
Volume | 56 |
Issue number | 5 |
DOIs | |
State | Published - Dec 1985 |
Externally published | Yes |