Nuclear quadrupole resonance

About: Nuclear quadrupole resonance is a research topic. Over the lifetime, 3531 publications have been published within this topic receiving 38801 citations. The topic is also known as: Nuclear quadrupole resonance spectroscopy & NQR.

Determination of the 14N electric field gradient tensor in the nitro group: A single crystal nuclear double resonance study of p‐nitrotoluene

Abstract: The 14N electric field gradient tensor in single crystalline p‐nitrotoluene has been determined at room temperature via proton–nitrogen double resonance in the rotating frame. The major principal (Z) axis of the tensor lies along the C–N bond axis. The quadrupole coupling constant (1340 kHz) and asymmetry parameter (0.408) determined from analysis of the rotation patterns are in excellent agreement with the values measured in a zero field double resonance experiment on powdered p‐nitrotoluene.

NQR of 35Cl in paramagnetic and antiferromagnetic K2IrCl6

Abstract: Measurements of the 35Cl nuclear quadrupole resonance as a function of temperature and magnetic field above the Neel point of K2IrCl6 are interpreted as providing no direct evidence of a proposed phase transition suggested to explain certain infrared measurements. The temperature dependence of the nqr lines is fitted to the simple Bayer theory, although the theory does not appear adequate for a complete description. Below the Neel point the nqr line splits into seven separate lines which can be explained in terms of transferred hyperfine interactions at each of the chlorine nuclei, in part due to the existence of molecular orbitals on the IrCl6 complexes. Deviations from the hyperfine interactions of the molecular orbitals suggest additional transferred hyperfine interactions from neighbouring ions of chlorine, which may be a result of the superexchange between iridium ions in the antiferromagnetic state.