We combined diamond anvil cell techniques, infrared and Raman spectroscopies, and lattice dynamics calculations to explore the high pressure properties of multiferroic Ni3TeO6. Using a frequency trend analysis, we trace a subtle decrease in compressibility near 4 GPa to a minimum in the O-Ni2-O bond angle. This unique behavior emanates from the proximity of the Ni2 center in the Ni3-Ni2-Ni1-Te chain to a flexible pocket that is intrinsic to the crystal structure. At the same time, predicted trends in the superexchange pathways are consistent with greater antiferromagnetic character under compression, in line with both phase stability calculations and direct susceptibility measurements. These findings highlight opportunities for local structure control of corundumlike materials.
Bibliographical noteFunding Information:
Research at the University of Tennessee and Rutgers University is supported by the NSF-DMREF program (DMR-1629079 and DMR-1629059). Work at the University of Minnesota is funded by the NSF-DMREF program as well (DMR-1629260). J.Y.'s work is supported by Central Michigan University. Work at the National Synchrotron Light Source at Brookhaven National Laboratory is funded by the Department of Energy (DE- AC98-06CH10886). The use of the U2A beamline is supported by COMPRES under NSF Cooperative Agreement EAR 11-57758 and CDAC (DE-FC03-03N00144).
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