We have developed an alternative to the internal chemical reference based on a calibrated reference
signal which is not a real NMR line but an electronically produced signal (HERETIC) and determined the
phosphorus concentration using this method. The area ratio of HERETIC and sample peaks obtained from the
standard samples was used to measure the concentrations of different samples directly. The analysis of
phosphorus by this method showed the excellent linear regression coefficient (R2=0.9999) for the concentration
range from 20 ppm to 500 ppm with HERETIC peak as reference.