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Updated: Jun 12, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Quantum-dynamical consequences of the permutation symmetry of methyl groups
Thomas Grohmann1, Monika Leibscher
1Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
Abstract:
We identify the nuclear spin isomers of nitromethane (CH(3)NO(2)) and discuss how symmetry arguments may be used to determine the spectrum and eigenfunctions of the spatial and spin-dependent Hamiltonians in an elegant way. Furthermore, we explore the effect of nuclear spin on the dynamics of the methyl group induced by a time-dependent magnetic field. We demonstrate that dipolar interactions between the protons can give rise to rotation of the methyl group and show within a one-dimensional model and first order time-dependent perturbation theory that the induced motion is unidirectional and nuclear-spin selective.
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