P–V–T equation of state of iridium up to 80 GPa and 3100 K

DOI: 10.3390/cryst11040452

Authors: Simone Anzellini (Diamond Light Source) , Leonid Burakovsky (Los Alamos National Laboratory) , Robin Turnbull (Universidad de Valencia) , Enrico Bandiello (Universidad de Valencia) , Daniel Errandonea (Universidad de Valencia)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Crystals , VOL 11

State: Published (Approved)
Published: April 2021
Diamond Proposal Number(s): 21610

Abstract: In the present study, the high-pressure high-temperature equation of the state of iridium has been determined through a combination of in situ synchrotron X-ray diffraction experiments using laser-heating diamond-anvil cells (up to 48 GPa and 3100 K) and density-functional theory calculations (up to 80 GPa and 3000 K). The melting temperature of iridium at 40 GPa was also determined experimentally as being 4260 (200) K. The results obtained with the two different methods are fully consistent and agree with previous thermal expansion studies performed at ambient pressure. The resulting thermal equation of state can be described using a third-order Birch–Murnaghan formalism with a Berman thermal-expansion model. The present equation of the state of iridium can be used as a reliable primary pressure standard for static experiments up to 80 GPa and 3100 K. A comparison with gold, copper, platinum, niobium, rhenium, tantalum, and osmium is also presented. On top of that, the radial-distribution function of liquid iridium has been determined from experiments and calculations.

Journal Keywords: iridium; equation of state; high pressure; X-ray diffraction; laser heating; density-functional theory; melting; radial-distribution function

Subject Areas: Chemistry


Instruments: I15-Extreme Conditions

Added On: 27/04/2021 08:25

Discipline Tags:

Physical Chemistry Chemistry

Technical Tags:

Diffraction X-ray Powder Diffraction