Numerical Design and Evaluation of Broadband Pulse Sequences for 1=1 spin systems
نویسندگان
چکیده
Quadrupolar coupling constants of 170 kHz result from reduced motional averaging in biological polymers. The decay rates of Zeeman and quadrupolar order are direct measures of the spectral densities of motion. Information on the orientation-dependence of relaxation rates of Zeeman and quadrupolar order, Tlz and Tlq respectively, assists in understanding the dynamics of molecules. Sensitivity and dynamic range considerations mandate optimum efficiency and uniformity over large spectral widths. The design of composite pulses to create broadband excitation and inversion is well established for deuterium NMR." The numerical optimization of existing composite inversion pulse sequences was performed in order to increase the uniformity of excitation over spectral widths of 250 kHz. "
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