Work

Testing the Ce Limit of Mass Bias Correction Using 145 Nd/ 142 Nd as Normalizing Ratio in Radiogenic Neodymium Isotope Analysis by MC‐ICP‐MS

Year: 2024

Type: article

Abstract: ABSTRACT Rationale Neodymium isotopes are a powerful geochemical tool that has widely been used in terrestrial and extraterrestrial studies. Modern multicollector inductively coupled plasma mass spectrometers (MC‐ICP‐MS) allow fast, accurate, and precise analysis of the radiogenic Nd isotope ratio 143 Nd/ 144 Nd. These analyses comprise relatively high instrumental mass bias that is typically corrected for using the stable 146 Nd/ 144 Nd of 0.7219 and an exponential law. The instrument is usually tuned to optimize the operating conditions for isotope analysis, but this tuning is a trade‐off primarily between signal intensity, stability, and accuracy. Alternative, more effective approaches for mass bias correction have been proposed that use 145 Nd/ 142 Nd as normalizing ratio. However, one drawback of using this ratio is that the efficient removal of Ce from Nd is required to minimize the effect of isobaric interference of 142 Ce on 142 Nd. Methods Here, we analyzed international Nd and rock reference materials using a Thermo Scientific Neptune Plus MC‐ICP‐MS to evaluate the sensitivity of 145 Nd/ 142 Nd‐based mass bias correction to varying Ce/Nd and in comparison with the commonly used 146 Nd/ 144 Nd‐based correction. Results Our results show that the corrected 143 Nd/ 144 Nd of Ce‐doped JNdi‐1 and Ce‐containing USGS BCR‐2, NOD‐A‐1, and NOD‐P‐1 reference materials are insensitive to Ce/Nd of up to ~1. Conclusions The correction of instrumental mass bias with 145 Nd/ 142 Nd as a normalizing ratio yields, as previously suggested, improved trueness and precision of 143 Nd/ 144 Nd data in comparison with 146 Nd/ 144 Nd‐based corrections, even under high Ce/Nd of ~1. This allows improved optimization of signal intensity during instrument tuning, which is particularly useful for natural samples with low Nd content. [Correction added on 10 December 2024, after first online publication: The Results and Conclusions in Abstract has been corrected in this version.]

Source: Rapid Communications in Mass Spectrometry

DOI: 10.1002/rcm.9951

Authors: Torben Struve, Martin Zander, Katharina Pahnke

Institutions: Carl von Ossietzky Universität Oldenburg, Institute for Chemistry and Biology of the Marine Environment

Language: English

Topic: Geological and Geochemical Analysis

Subfield: Geophysics

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,840

Funders: Bundesministerium für Bildung und Forschung, Federalno Ministarstvo Obrazovanja i Nauke, Bundesministerium für Bildung, Wissenschaft und Forschung