Abstract
The high-pressure behavior of the natural arsenate gasparite-(Ce) [Ce0.43La0.24Nd0.15Ca0.11Pr0.04Sm0.02Gd0.01(As0.99Si0.03O4)] from the Mt. Cervandone mineral deposit (Piedmont Lepontine Alps, Italy), has been studied by in situ single-crystal synchrotron X-ray diffraction up to 22.01 GPa. Two distinct high-pressure ramps have been performed, using a 16:3:1 methanol:ethanol:water solution and helium as P-transmitting fluids, respectively. No phase transition occurs within the pressure range investigated, whereas a change in the compressional behavior has been observed at ~ 15 GPa. A second-order Birch-Murnaghan EoS was fitted to the P-V data, leading to a refined bulk modulus of 109.4(3) GPa. The structural analysis has been carried out on the basis of the refined structure models, allowing the description of the deformation mechanisms accommodating the bulk compression in gasparite-(Ce) at the atomic scale, which is mainly controlled by the compression of the Rare Earth Elements coordination polyhedra, while the AsO4 tetrahedra behave as a quasi-rigid units. A micro-Raman spectroscopy analysis, performed at ambient conditions, suggests the presence of hydroxyl groups into the structure of the investigated gasparite-(Ce).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
