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Article: CHARACTERIZING NANOSCOPIC DISORDER USING QUANTUM MOLECULAR TOPS.(Brief Article)
- Article from:
- Journal of Research of the National Institute of Standards and Technology
- Article date:
- March 1, 2001
CopyrightCOPYRIGHT 2001 National Institute of Standards and Technology. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Researchers at the NIST Center for Neutron Research (NCNR) have recently carried out the first U.S. studies by cold neutron spectroscopy of molecular disorder induced by nanoscale confinement. In this work inelastic neutron scattering was used to probe the rotational dynamics of molecules adsorbed into porous glass disks with pores ranging from 2.5 nm to 7.5 nm.
In bulk molecular solids at [approximate]5 K, the molecular rotors are classically forbidden from rotating due to the surrounding molecular field. However, quantum mechanics allows the molecules to rotate by tunneling through the barrier. The differences observed between the quantum tunneling in the bulk ...