A General Numerical Analysis of Time-Domain NQR Experiments

Journal Article · Fri Dec 01 04:00:00 EST 2006 · Journal of Magnetic Resonance, 183(2):308-314

DOI:https://doi.org/10.1016/j.jmr.2006.06.033· OSTI ID:897383

Harel, Elad; Cho, Herman M

We introduce a general numerical approach for solving the Liouville equation of a quadrupolar nuclide that we show can be used to analyze time-domain NQR experiments. A computer-based treatment is necessitated by the dimensionality of the Liouville space, which precludes analytical, closed form solutions for I > 3/2. Accurate simulations of experimental nutation curves, forbidden transition intensities, powder and single crystal spectra, and off-resonance irradiation dynamics can be computed with this method. We also examine the validity of perturbative approximations where the signal intensity of a transition is proportional to the transition moment between the eigenstates of the system, thus providing a simple basis for determining selection rules. Our method allows us to calculate spectra for all values of the asymmetry parameter, ?, and sample orientations relative to the coil axis. We conclude by demonstrating the methodology for calculating the response of the quadrupole system to amplitude- and frequency-modulated pulses.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 897383
• Report Number(s): PNNL-SA-48983
• Journal Information: Journal of Magnetic Resonance, 183(2):308-314, Journal Name: Journal of Magnetic Resonance, 183(2):308-314
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
ASYMMETRY
BOLTZMANN-VLASOV EQUATION
FORBIDDEN TRANSITIONS
IRRADIATION
Liouville equation
MONOCRYSTALS
NQR
NUMERICAL ANALYSIS
QUADRUPOLES
SELECTION RULES
SPECTRA
interaction representation
time-dependent perturbation theory
time-domain nuclear quadrupole resonance