The calibration of Si isotope ratio measurements

Abstract

The determination of absolute isotope amount ratios requires the calibration of mass spectrometric measurements. In this paper, for the first time, the relevant calibration factors are given via exact analytical equations. It extends the results of a previous investigation, based on a simple two-isotope model, to a three-isotope system. Particular emphasis is given to silicon, because of its role in the determination of the Avogadro constant. The conditions ensuring the existence and uniqueness of the calibration-equation solutions are related as well.