Articles | Volume 38, issue 6
https://doi.org/10.5194/ejm-38-669-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ejm-38-669-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
New insights into the high-pressure behaviour of the cyclosilicate benitoite, BaTiSi3O9
Benedetta Chrappan Soldavini
Dipartimento di Scienze della Terra, Università degli Studi di Milano, Via Botticelli 23, 20133 Milano, Italy
Dipartimento di Scienze della Terra, Università degli Studi di Milano, Via Botticelli 23, 20133 Milano, Italy
Gaston Garbarino
ESRF – European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS40220, 38043 Grenoble CEDEX, France
Michael Hanfland
ESRF – European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS40220, 38043 Grenoble CEDEX, France
Marco Merlini
Dipartimento di Scienze della Terra, Università degli Studi di Milano, Via Botticelli 23, 20133 Milano, Italy
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Short summary
The high-pressure behavior of benitoite was studied by synchrotron single-crystal X-ray diffraction up to 22.3 GPa. Three phase transitions were identified: benitoite → II (3.9–4.4 GPa), II → III (12.4–13.1 GPa), and III → IV (16.4–17.1 GPa). Structural evolution and deformation mechanisms are reported, highlighting Si₃O₉ ring rearrangements. These results clarify ring stabilization in silicates and offer analogues for high-pressure CaSiO₃ phases and sp³ carbonates in planetary interiors.
The high-pressure behavior of benitoite was studied by synchrotron single-crystal X-ray...