Energy-dispersive x-ray diffraction with synchrotron radiation at cryogenic temperatures

Abstract

A facility is described which has been developed for the rapid acquisition of structural information through the use of heterochromatic synchrotron radiation from a sample pressurized in a diamond-anvil cell and simultaneously cooled to cryogenic temperature. The system employs a closed-cycle He refrigerator, which can be continuously operated, independent of any liquid cryogens, from a remote station. The compressive contact force between the diamonds, and hence the sample pressure, is also externally controlled, thereby providing remote control capabilities for both the pressure and temperature. NaCl has been used as an internal pressure calibrant and existing empirical equation-of-state calculations for NaCl have been extended to reduced temperatures for this purpose. Preliminary data on the lower pressure critical point associated with the isomorphic phase transition in Ce0.8Th0.1La0.1 are presented.

High pressure magnetic transition in pyrrhotite and impact demagnetization on Mars

“…A pressure up to about 2GPa could be applied on the sample during the D1B measurements while a maximum of about 3GPa could be reached during the D20 measurements. A small amount of NaCl was added to the sample for absolute calibration of the pressure [ Skelton et al , 1984]. Deuterated ethanol was used as a pressure transmitting media to insure a homogeneous pressure.…”

A novel diamond anvil cell for x-ray diffraction at cryogenic temperatures manufactured by 3D printing

“…Data collections were then carried out at room temperature and 120 K as described above and the pressure was confirmed to be 1.7 GPa, from the NaCl equation of state (EOS). 27 The estimated pressure was further corroborated against the low temperature highpressure EOS of HMT-d 12 28 and found to be consistent within 0.05 GPa.…”

Deuteration and pressure effects on the crystal structure of paraelectric NH4H2PO4

“…The measured contraction in the lattice dimension of the NaCl pressure calibrant was 1.64(3)% at a temperature of 130 K, which corresponds to a pressure of 8.9(4) kbar (Skelton, Webb, Qadri, Wolf, et al, 1984). The measured contraction in the lattice dimension of the NaCl pressure calibrant was 1.64(3)% at a temperature of 130 K, which corresponds to a pressure of 8.9(4) kbar (Skelton, Webb, Qadri, Wolf, et al, 1984).…”