Roto-electrics: Three Dimensional Dipolar Molecular Rotor Lattices
Abstract
We have synthesized and characterized a series of three-dimensional crystals in which each unit cell contains a polar benzene rotator surrounded by bulky triphenyl cages. Substituents of varying electronegativities alter the rotator dipole moment. Materials of this type may have useful dielectric functions, and they offer an orientable functional element for molecular switches and memories. Through dielectric spectroscopy supported by CPMAS NMR and X-ray diffraction, we access the potential energy surface, which determines the rotor dynamics, including rotational barriers and well energies. We find rotor orientation for a non-symmetrical rotor to be dominated by rotor-lattice interactions. For a symmetrical rotor with a larger dipole moment, dipole-dipole interactions are observed indicating that interesting collective behavior can be engineered into these systems.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARP37008H