title: The Absolute Isotopic Composition and Atomic Weight of Terrestrial Nickel.
abstract: Twenty-nine samples of high-purity nickel metals, reagent salts and minerals, collected from worldwide sources, have been examined by high-precision isotope ratio mass spectrometry for their nickel isotopic composition. These materials were compared directly with SRM 986, certified isotopie standard for nickel, using identical measurement techniques and the same instrumentation. This survey shows no statistically significant variations among the samples investigated, indicating that the certified atomic weight and associated uncertainty for SRM 986 is applicable to terrestrial nickel samples. The atomic weight calculated for SRM 986 is 58.69335±0.00015 [2]. The currently recommended IUPAC value for terrestrial nickel is 58.69±0.01.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: J W
authors.initials: JW
authors.lastname: Gramlich
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: E S
authors.initials: ES
authors.lastname: Beary
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: L A
authors.initials: LA
authors.lastname: Machlan
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: I L
authors.initials: IL
authors.lastname: Barnes
keywords: SRM 986; Standard Reference Materials; absolute ratio; atomic weight; isotopie abundance; mass spectrometry; nickel; terrestrial samples