Abstract
A new polymorph of the RE2Ru3Ge5 (RE = Pr, Sm, Dy) compounds has been grown as single crystals via an indium flux. These compounds crystallize in tetragonal space group P4/mnc with the Sc2Fe3Si5-type structure, having lattice parameters a = 11.020(2) Å and c = 5.853(1) Å for RE = Pr, a = 10.982(2) Å and c = 5.777(1) Å for RE = Sm, and a = 10.927(2) Å and c = 5.697(1) Å for RE = Dy. These materials exhibit a structural transition at low temperature, which is attributed to an apparent charge density wave (CDW). Both the high-temperature average crystal structure and the low-temperature incommensurately modulated crystal structure (for Sm2Ru3Ge5 as a representative) have been solved. The charge density wave order is manifested by periodic distortions of the one-dimensional zigzag Ge chains. From X-ray diffraction, charge transport (electrical resistivity, Hall effect, magnetoresistance), magnetic measurements, and heat capacity, the ordering temperatures (TCDW) observed in the Pr and Sm analogues are ∼200 and ∼175 K, respectively. The charge transport measurement results indicate an electronic state transition happening simultaneously with the CDW transition. X-ray absorption near-edge spectroscopy (XANES) and electronic band structure results are also reported.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 4130-4143 |
| Number of pages | 14 |
| Journal | Journal of the American Chemical Society |
| Volume | 139 |
| Issue number | 11 |
| DOIs | |
| State | Published - Mar 22 2017 |
Funding
Work at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Materials Sciences and Engineering. Use of the Advanced Photon Source and the Center for Nanoscale Materials, including the Electron Microscopy Center, at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Sector 20 operations at the Advanced Photon Source were supported by the U.S. Department of Energy and the Canadian Light Source. Single-crystal X-ray diffraction work (modulated structure at 175 K) made use of the Integrated Molecular Structure Education and Research Center (IMSERC) at Northwestern University, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF NNCI-1542205), the State of Illinois, and the International Institute for Nanotechnology (IIN). Research conducted at the Cornell High Energy Synchrotron Source (CHESS) was supported by the National Science Foundation and the National Institutes of Health/National Institute of General Medical Sciences under NSF award DMR-1332208. Work at Ames Laboratory was supported by the U.S. Department of Energy, Basic Energy Sciences, Division of Materials Sciences and Engineering. under Contract No. DE-AC02-07CH11358. Computational work was done using resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility, supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-05CH11231. We would like to thank Saul Lapidus for his assistance during the data collection at Sector 11-BM of the APS, Omar Chmaissem for his aid with the synchrotron single-crystal X-ray diffraction measurements, and Justin Wozniak for his assistance with the processing of the synchrotron single-crystal X-ray diffraction data.
ASJC Scopus subject areas
- General Chemistry
- Biochemistry
- Catalysis
- Colloid and Surface Chemistry
