Nuclear Quadrupole Resonance Investigation of Phase Transition in Tetramethylammonium Cadmium Tribromide

Effect of Deuteration on Ammonium Motion and Structural Phase Transition Studied by Nuclear Quadrupole Resonance

Cl NQR measurements revealed two phase transitions at 14.5 K and 70 K in NH4ICl4. By deuteration of the ammonium ions, the respective transition temperature increased to 27 K and 74 K. In the lowest-temperature phase of NH4ICl4, by the deuteration a remarkable change of the temperature dependence of the Cl NQR frequencies was observed. The NQR spin-lattice relaxation-time minimum, ascribable to...

Structural Phase Transition of N,N-Dimethylnitramine as Studied by 14N Nuclear Quadrupole Resonance*

für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...

Nuclear Quadrupole Resonance*

A resonance phenomenon which is closely related to NMR is nuclear quadrupole resonance (NQR), which was discovered in 1950 by Dehmelt and Kruger. All nuclei with a spin > 1 possess in addition to the magnetic moment, an electric quadrupole moment eQ, which measures the deviation of the distribution of the positive charge in the nucleus from spherical symmetry. While e is the elementary charge, ...

Nuclear Quadrupole Resonance Spectroscopy

Nuclear Quadrupole Resonance (paper Ii)

The Polymer Diagnostics Section (Code 6122) of the U.S. Naval Research Laboratory (NRL) has expertise in solid state nuclear magnetic resonance (NMR), magnetic resonance imaging (MRI), and nuclear quadrupole resonance (NQR). In 1983, NRL established an interagency agreement with the Federal Aviation Administration (FAA) to advise the FAA on NMR methods to detect explosives. We were aware of ear...