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Pressure-induced normal-incommensurate and incommensurate-commensurate phase transitions in CrOCl.

ABSTRACT: The high-pressure behavior of layered CrOCl is shown to be governed by non-bonded interactions between chlorine atoms in relation to a rigid framework composed of Cr and O atoms. The competition between optimizing intra- and interlayer Cl-Cl distances and the general trend towards denser packing defines a novel mechanism for high-pressure phase transitions of inorganic materials. CrOCl possesses an incommensurate phase for 16-51 GPa. Single-crystal x-ray diffraction in a diamond anvil cell provides an accurate description of the evolution of the incommensurate wave with pressure. It thus demonstrates a continuous increase of the amplitude up to 30 GPa, followed by a decrease of the wavelength until a lock-in transition occurs at 51 GPa.

SUBMITTER: Bykov M

PROVIDER: S-EPMC4440982 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Pressure-induced normal-incommensurate and incommensurate-commensurate phase transitions in CrOCl.

Bykov Maxim M Bykova Elena E Dubrovinsky Leonid L Hanfland Michael M Liermann Hanns-Peter HP van Smaalen Sander S

Scientific reports 20150521

The high-pressure behavior of layered CrOCl is shown to be governed by non-bonded interactions between chlorine atoms in relation to a rigid framework composed of Cr and O atoms. The competition between optimizing intra- and interlayer Cl-Cl distances and the general trend towards denser packing defines a novel mechanism for high-pressure phase transitions of inorganic materials. CrOCl possesses an incommensurate phase for 16-51 GPa. Single-crystal x-ray diffraction in a diamond anvil cell provi ...[more]

PMID: 25999303

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