The SuperCam instrument suite onboard the Mars 2020 Perseverance rover uses the laser-induced breakdown spectroscopy (LIBS) technique to determine the elemental composition of rocks and soils of the Mars surface. It is associated with a microphone to retrieve the physical properties of the ablated targets when listening to the laser-induced acoustic signal. In this study, we report the monitoring of laser-induced mineral phase transitions in acoustic data.
View Article and Find Full Text PDFPyrite is a ubiquitous mineral in reducing environments and is well-known to incorporate trace elements such as Co, Ni, Se, Au, and commonly As. Indeed, As-bearing pyrite is observed in a wide variety of sedimentary environments, making it a major sink for this toxic metalloid. Based on the observation of natural hydrothermal pyrites, As is usually assigned to the occupation of tetrahedral S sites, with the same oxidation state as in arsenopyrite (FeAsS), although rare occurrences of As and As have been reported.
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
February 2015
The crystal structure of a specimen of `Pb-rich' chabournéite from Jas Roux, Hautes-Alpes, France, with the chemical formula obtained by electron microprobe analysis of Ag(0.04 (1))Tl(2.15 (2))Pb(0.
View Article and Find Full Text PDFX-ray standing waves (XSW) in a thin epitaxic film are treated in the framework of the dynamical theory. It is demonstrated that the fluorescence yield around the main peak of the rocking curve has essentially the same characteristics as that of the usual XSW on a bulk crystal surface. Thus, XSW provide a direct method to probe the atom position in a thin film.
View Article and Find Full Text PDF