FWHM: full width at half maximum; The 13C satellite signals of adjacent integrals sometimes could interfere with impurity signals for example, voiding the accuracy of integration. One solution is to adopt 13C decoupled pulse sequence to avoid unnecessary interferences.144 However, due to the limitation of some NMR instruments, 13C decoupled pulse sequence may be unavailable. If so, the investigation on specificity must be performed thoroughly.
Reference/Book Chapter: Quantitative NMR in Qulality Control
in Quality Control of Chinese Medicines-Strategies and Methods