Rotational dynamics of methyl groups in durene: A crystallographic, spectroscopic, and molecular mechanics investigation

Journal article

Neutron powder diffraction measurements of perdeutero durene in the temperature range from 1.5 K to 290 K have been performed. The lowest temperature structure is the starting point for calculations of the methyl group tunneling and librational dynamics. Ab initio methods and atom-atom potentials are used to determine rotational single particle and coupling potentials. Tunneling splittings and librational bands are calculated by numerical solution of Schrödinger's equation for a system of many coupled methyl groups. High-resolution inelastic neutron scattering measurements of methyl tunneling and molecular vibrations have been repeated, the tunneling results resolving an inconsistency with earlier NMR work. Quantum molecular dynamics provide a stringent test of the numerical methods and the data are ultimately well reproduced. These results are also discussed in the context of optical measurements of dye molecules in a host lattice of durene. © 1999 American Institute of Physics.

Authors: Neumann, M; Johnson, MR; Radaelli, P; Trommsdorff, H; Parker, S

• Publication status: Published
• Journal: JOURNAL OF CHEMICAL PHYSICS
• Volume: 110
• Issue: 1
• Pages: 516-527
• Publication date: 1999-01-01
• DOI: 10.1063/1.478137
• ISSN: 0021-9606
• Language: English