Evidence of Phase Transitions in MoO2 single crystals
Abstract
In this work, physical and structural properties are revisited in the MoO2 compound. MoO2 single crystals were grown by chemical vapor transport. Heat capacity and electrical resistance as a function of temperature were performed using a 9 T cryo-free Physical Properties Measurement System (PPMS). Thermal expansion (TE) was measured using a high-resolution capacitive dilatometer cell constructed from fused quartz. High-resolution Synchrotron x-ray powder diffraction was measured using a Shimazu diffractometer (XRD 6000) at several temperatures in the Brazilian Synchrotron Light Laboratory. Furthermore, Neutron powder diffraction data were collected using the BT-1 32 detector neutron powder diffractometer at the NIST. Electrical resistivity, heat capacity, and TE measurements show two clear features near 220 K and 267 K suggesting two phase transitions in MoO2 compound. The transition at 267 K has been related to a structural phase transition by high resolution synchrotron x-ray diffratometry measurements. Low temperature neutron diffraction measurements suggest that the phase transition near 220 K is electronic or magnetic in nature.
Thanks to FAPESP, CNPq CAPES, FAPEMIG, NSF and NIST.- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2017
- Bibcode:
- 2017APS..MAR.T1076D