The new technique for the measurement of isotope abundance of 143Nd without chemical removal of other rare earth elements.

Abstract

The 147Sm-143Nd isotopic system has been used as a powerful geochronological tool. Usually the 143Nd abundances has been obtained as the 143Nd/144Nd ratio. In this report, we will propose a new technique to measure 143Nd. In this new method, the amount of 143Nd is measured as the 143Nd/145Nd ratio and the 146Nd/145Nd ratio is used for the correction of mass fractionation. The normalizing value for 146Nd/145Nd ratio has been determined to be 2.07199. This technique will require no separation of Nd from other rare earth elements, since the stable nuclides with mass numbers of 143, 145, and 146 exist only in Nd. Furthermore, it seems that this new technique would be compatible with the old technique, where the data have been obtained as 143Nd/144Nd and normalized to 146Nd/144Nd=0.7219 after complete separation of Nd from mass-spectrometrically interfering REE.