title: Simultaneous hydrogen and heavier element isotopic ratio images with a scanning submicron ion probe and mass resolved polyatomic ions.
abstract: In situ microanalysis of solid samples is often performed using secondary ion mass spectrometry (SIMS) with a submicron ion probe. The destructive nature of the method makes it mandatory to prevent information loss by using instruments combining efficient collection of secondary ions and a mass spectrometer with parallel detection capabilities. The NanoSIMS meets those requirements with a magnetic spectrometer but its mass selectivity has to be improved for accessing opportunities expected from polyatomic secondary ions. We show here that it is possible to perform D/H ratio measurement images using 12CD-/12CH-, 16OD-/16OH-, or 12C2D-/12C2H- ratios. These polyatomic species allow simultaneous recording of D/H ratios and isotopic compositions of heavier elements like 15N/14N (via 12C15N-/12C14N-) and they provide a powerful tool to select the phase of interest (e.g., mineral versus organics). We present high mass resolution spectra and an example of isotopic imaging where D/H ratios were obtained via the 12C2D-/12C2H- ratio with 12C2D- free from neighboring mass interferences. Using an advanced mass resolution protocol, a "conventional" mass resolving power of 25,000 can be achieved. Those results open many perspectives for isotopic imaging at a fine scale in biology, material science, geochemistry, and cosmochemistry.
authors.affiliation: 1 Centre de Sciences Nucléaires et de Sciences de la Matière, CNRS-IN2P3 and Université Paris-Sud, F-91405 Orsay Cedex, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Slodzian
authors.affiliation: 2 Institut Curie, Laboratoire de Microscopie Ionique, 91405 Orsay, France.
authors.forename: Ting-Di
authors.initials: TD
authors.lastname: Wu
authors.affiliation: 1 Centre de Sciences Nucléaires et de Sciences de la Matière, CNRS-IN2P3 and Université Paris-Sud, F-91405 Orsay Cedex, France.
authors.forename: Noémie
authors.initials: N
authors.lastname: Bardin
authors.affiliation: 1 Centre de Sciences Nucléaires et de Sciences de la Matière, CNRS-IN2P3 and Université Paris-Sud, F-91405 Orsay Cedex, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Duprat
authors.affiliation: 1 Centre de Sciences Nucléaires et de Sciences de la Matière, CNRS-IN2P3 and Université Paris-Sud, F-91405 Orsay Cedex, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Engrand
authors.affiliation: 2 Institut Curie, Laboratoire de Microscopie Ionique, 91405 Orsay, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Guerquin-Kern