AI Article Synopsis
- The study focuses on the rf pulse response in a I = 3/2 spin system with first-order quadrupolar splitting, utilizing a density matrix approach to derive a general expression for NMR signals from center line and satellite resonances.
- The research derives a transformation matrix from the Hamiltonian to analyze the center line response, while satellite signals are computed using numerical values from quartic equations.
- The paper also examines how the widths of π/2-pulses vary with initial spin populations and explores the relationship between pulse width, signal amplitude, and satellite splitting.
Article Abstract
The rf pulse response of I = 3/2 spin system experiencing first order quadrupolar splitting is studied using density matrix approach. A general expression is derived in terms of spin populations, quadrupole splitting and duration and amplitude of the rf pulse for calculating the NMR signal arising due to the centre line and satellite resonances for the situation where the impressed rf pulse excites the resonances selectively as well as non-selectively. The necessary 4 X 4 transformation matrix obtained analytically by diagonalyzing the Hamiltonian are used to get the expression for the centre line response. The satellite signals are obtained in the same way but by using the numerical values of the roots of the related quartics. The widths of the corresponding pi/2-pulses are calculated for different initial spin populations. The variations of this pulse-width and the corresponding signal amplitude as a function of satellite splitting are studied.
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| http://dx.doi.org/10.1016/s0926-2040(00)00077-1 | DOI Listing |
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