skip to main content

DOE PAGESDOE PAGES

Title: Structural behavior of ZnCr 2S 4 spinel under pressure

Here, the series of Cr-chalcogenide spinels ACr 2X 4 (A = Zn, Cd, Hg; X = S, Se) exhibits a rich phase diagram upon compression, as revealed by our recent investigations. There exist, however, some open questions regarding the role of cations in the observed structural transitions. In order to address these queries, we have performed X-ray diffraction and Raman spectroscopic studies on the ZnCr 2S 4 spinel up to 42 GPa, chosen mainly due to the similarity of the Zn 2+ and Cr 3+ cationic radii. Two reversible structural transitions were identified at 22 and 33 GPa, into a I4 1/ amd and an orthorhombic phase, respectively. Close comparison with the behavior of relevant Cr-spinels revealed that the structural transitions are mainly governed by the competition of the magnetic exchange interactions present in these systems, and not by steric effects. In addition, careful inspection of the starting Fd$$\bar{3}$$m phase revealed a previously unnoticed isostructural transition. The latter is intimately related to changes in the electronic properties of these systems, as evidenced by our Raman studies. Our results provide insights for tuning the physical and chemical properties of these materials, even under moderate compression, as well as promoting the understanding of similar pressure-induced effects in relevant systems.
Authors:
ORCiD logo [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [2]
  1. Oakland Univ., Rochester, MI (United States). Dept. of Physics; Deutsches GeoForschungsZentrum GFZ, Potsdam (Germany)
  2. Oakland Univ., Rochester, MI (United States). Dept. of Physics
  3. Academy of Sciences of Moldova (Moldova). Inst. of Applied Physics; Univ. of Augsburg (Germany). Center for Electronic Correlations and Magnetism, Inst. of Physics
  4. Univ. of Augsburg (Germany). Center for Electronic Correlations and Magnetism, Inst. of Physics
  5. Academy of Sciences of Moldova (Moldova). Inst. of Applied Physics
Publication Date:
Grant/Contract Number:
AC02-06CH11357; NA0001974; FG02-99ER45775; FG02-94ER14466
Type:
Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 121; Journal Issue: 1; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Research Org:
GeoForschungsZentrum Potsdam (Germany); Oakland Univ., Rochester, MI (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE
OSTI Identifier:
1340640