Berlin 2024 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MA: Fachverband Magnetismus

MA 45: Spin Structures and Magnetic Phase Transitions II

MA 45.4: Talk

Thursday, March 21, 2024, 15:45–16:00, EB 407

Proton disorder in the double hydroxide perovskite CuSn(OH)₆ under hydrostatic pressure. — •Nikolai Pavlovskii¹, Anton Kulbakov¹, Kaushick Krishnakanta Parui¹, Darren C. Peets¹, Thomas Doert², Thomas Hansen³, Ellen Häusler², Ines Puente-Orench³, Vladimir Pomjakushin⁴, and Dmytro S. Inosov¹ — ¹IFMP, TU Dresden, Germany — ²Anorg. Chemie II, TU Dresden, Germany — ³ILL, France — ⁴PSI, Switzerland

The understanding of proton disorder in materials beyond water ice is useful for the discovery of unique quantum phenomena. We present a comprehensive study of CuSn(OH)₆ (mineral name: mushistonite), a double hydroxide perovskite. Based on both X-ray and neutron diffraction studies, we have solved crystal structure of the synthetic deuterated compound CuSn(OD)₆ - Pnnn. At the same time, we have identified a strong disorder at all the deuterium sites. Furthermore, no magnetic Bragg peaks were found down to 50 mK, indicating that proton disorder may play a significant role in suppressing long-range magnetic ordering in this system, suggesting a ground state similar to that of a quantum spin liquid. It also motivates a pressure dependent investigation. Our experimental results reveal the structural nuances of CuSn(OD)₆ under varying pressures within a Paris-Edinburgh cell and shed light on potential structural phase transitions associated with proton ordering.

Keywords: Perovskite; High-pressure; Neutron diffraction