NICOLA BONINI
Articles written in Bulletin of Materials Science
Volume 45 All articles Published: 22 September 2022 Article ID 0186
New structural systematics in the lanthanide elements at high pressure
MALCOLM I MCMAHON SARAH E FINNEGAN EDWARD J PACE CHRISTIAN V STORM MICHAEL G STEVENSON SIMON G MACLEOD EVGENY PLEKHANOV NICOLA BONINI CEDRIC WEBER
The pressure-induced structural phase transitions in the lanthanide elements provide insight into changes in their electronic structures at high densities. After a series of transitions via close-packed structures, the regular trivalent lanthanides (La to Lu, excluding Ce, Eu and Yb) undergo first-order transitions to so-called collapsed phases, the structures of which have long been reported as monoclinic. However, the diffraction data from these phases are not wellfitted by this monoclinic structure, and the patterns from Nd and Sm are distinctly different to those from the higher-Z lanthanides (Gd${\rightarrow}$). Here we present results from recent diffraction studies on Tb, Gd, Sm, Nd and Y to above 300 GPa,which reveal that there are two different collapsed structures, neither of which is monoclinic. High-precision equation of state studies of the same elements reveal distinct changes in compressibility once the collapsed phases are obtained. Wealso show that these new structures are strikingly similar to those observed in the higher-Z actinides at high pressure, greatly strengthening the structural systematics of the 4f and 5f elements.
Volume 46, 2023
All articles
Continuous Article Publishing mode
Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
Click here for Editorial Note on CAP Mode
© 2022-2023 Indian Academy of Sciences, Bengaluru.