Gadolinium isotopic measurements by surface ionization mass spectrometry

Abstract

Gadolinium isotope ratio measurements were carried out by single filament thermal ion source, with the addition of colloidal carbon as surface and chemical modifier. The technique becomes an interesting alternative to classical single filament GdO⁺ and triple filament Gd⁺ analysis. The methodology developed has been applied to a sample containing Gd₂O₃ which was converted to nitrate before loading it on a rhenium filament. Optimum Gd⁺ ion signal is produced at a temperature of 1470δC. The measured mean isotopic ratios agree with the representative isotopic composition reviewed and reported by IUPAC. Typical relative external standard deviations of 0.2% are attainable for the¹⁵⁷Gd abundance.