We can also show that for I = 3/2, only two levels (one NQR transition) can be observed. NOTE NQR must be done on solid samples, for molecular tumbling in liquids averages field gradients to zero. Sample must also be diamagnetic (unpaired electrons affect relaxation times of nuclei). Some examples.... AsR3 compounds.

1999年12月31日 · Nuclear quadrupole resonance (NQR) spectra of 17O, 39K, 85Rb, 87Rb and 133Cs have been measured in the low-temperature phases of KHSO4, RbHSO4, NH4HSO4 and TlHSO4 with the nuclear...

Nuclear quadrupole resonance spectroscopy or NQR is a chemical analysis technique related to nuclear magnetic resonance (NMR). Unlike NMR, NQR transitions of nuclei can be detected in the absence of a magnetic field, and for this reason NQR spectroscopy is …

2010年1月1日 · When applied to structural investigations, NQR spectra may prove an effective tool for preliminary study of crystal structure in the absence of detailed X-Ray data. Such parameters as...

2020年11月1日 · Nuclear quadrupole resonance (NQR) represents a solid-state radio frequency (RF) technique used in chemical analysis that was first observed in 1949, by H. Dehmelt and H. Krüger [1]. Its working principle is based on RF excitation of quadrupolar nuclei with quantum spin number greater than 1.

2021年10月12日 · The identification of the NQR response signal is a binary classification problem (detected/not detected) and this study aims to propose new signal analysis solutions in order to improve the detection performance.

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NQR spectroscopy is a well-established method providing information about molecular motion in solid state. The great advantage of NQR spectroscopy is that (in most cases) it directly reflects dynamics of the molecule carrying the nucleus of interest (since quadrupolar interactions are a single-spin interaction as already pointed out).

2020年5月31日 · It is suitable for the study of measured (poly)crystalline chemical compounds containing quadrupole nuclei (nuclei with spin I ≥ 1) where the characteristic NQR frequencies represent the...

• Nuclear quadrupole resonance (NQR) uses radio-frequency (RF) magnetic fields to induce and detect transitions between sublevels of a nuclear ground state. • Nuclei carrying NQR are able to absorb energy from EMR at frequency region 1-1000 …