Equation of state measurements by radiography provide evidence for a liquid-liquid phase transition in cerium

18th APS-SCCM; 24th AIRAPT

Lipp, M.J.^1 ; Jenei, Zs^1 ; Ruddle, D.^1 ; Aracne-Ruddle, C.^1 ; Cynn, H.^1 ; Evans, W.J.^1 ; Kono, Y.^2 ; Kenney-Benson, C.^2 ; Park, C.^2

Lawrence Livermore National Laboratory, Livermore

CA

94550, United States^1

HPCAT, Geophysical Laboratory, Carnegie Institution of Washington, Argonne

IL

60439, United States^2

关键词: Cell assembly;    Energy dispersive x-ray diffractions;    Equation of state;    Inflection points;    Large volume press;    Liquid liquid phase transitions;    Pressure volumes;    Rectangular shapes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/3/032011/pdf
DOI  :  10.1088/1742-6596/500/3/032011

来源: IOP

【 摘 要 】

A pressure-volume isotherm in cerium metal at 1100 K was measured in a large volume press of the Paris-Edinburgh type up to 6 GPa. The volume was determined by imaging a rectangular shape of the sample via white X-ray radiography. Energy dispersive x-ray diffraction spectra were recorded to ensure that the highly reactive cerium in the cell assembly remained pure at this temperature. Even at 1100 K the p-V equation of state of liquid cerium shows a pronounced decrease of the bulk modulus above the y-phase region similar to the 775 K isotherm in the solid that also shows an inflection point between y- and a-type cerium. The inflection point in the 1100 K isotherm indicating the minimum in the bulk modulus separating the γ- from the α-type liquid is located at approximately 3.5 GPa.