Here, we present an improved version of Q-DEPT (Q-DEPT (+)) and a quantitative POMMIE (Q-POMMIE) where the cyclic delays and read pulse phases are applied. However, the optimization is incomplete for the SI 2 and SI 3 systems. 2004, 126, 3682-3683), and satisfactory results for SI system are achieved. To overcome these problems, Henderson proposed a quantitative DEPT (Q-DEPT) method by cycling selected read pulse angles and polarization-transfer delays (Henderson, T. The sensitivity can be enhanced with DEPT and INEPT approaches by transferring polarization from (1)H (I) to (13)C (S), but since the enhancements depend on coupling constants ( (1) J SI) and spin systems (SI, SI 2, SI 3), the enhancements for different spin systems are not uniform and quantitative analyses are seriously affected.
However, due to the lower sensitivity and longer relaxation time, (13)C NMR experiment takes much longer time to obtain a spectrum with adequate signal-to-noise ratio. In quantitative analysis, inverse gated (1)H decoupled (13)C NMR provides higher resolution than (1)H NMR.
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