TY - JOUR

T1 - Isostructural crystal hydrates of rare-earth metal oxalates at high pressure

T2 - From strain anisotropy to dehydration

AU - Zakharov, Boris A.

AU - Gribov, Pavel A.

AU - Matvienko, Alexander A.

AU - Boldyreva, Elena V.

PY - 2017/10/26

Y1 - 2017/10/26

N2 - The crystal structures of a series of isostructural rare-earth metal oxalates, (REE)2(C2O4)3·10H2O (REE=Sm, Y) and a 1:1 YSm(C2O4)3·10H2O solid solution, have been studied in situ by single-crystal X-ray diffraction and optical microscopy. The structures were followed from ambient pressure to 6 GPa in a DAC with paraffin as the hydrostatic fluid. Bulk compressibilities, anisotropic lattice strain on hydrostatic compression and the corresponding changes in the atomic coordinates were followed. Discontinuities/sharp changes in the slopes of the pressure dependences of volume and selected cell parameters have been observed for yttrium-containing salts at 3.5 GPa. This may be related to the re-distribution of water molecules within the crystal structure. Y2(C2O4)3·10H2O undergoes a partial dehydration at 1 GPa, forming monoclinic Y2(C2O4)3·6H2O as single-crystalline inclusions in the original phase.

AB - The crystal structures of a series of isostructural rare-earth metal oxalates, (REE)2(C2O4)3·10H2O (REE=Sm, Y) and a 1:1 YSm(C2O4)3·10H2O solid solution, have been studied in situ by single-crystal X-ray diffraction and optical microscopy. The structures were followed from ambient pressure to 6 GPa in a DAC with paraffin as the hydrostatic fluid. Bulk compressibilities, anisotropic lattice strain on hydrostatic compression and the corresponding changes in the atomic coordinates were followed. Discontinuities/sharp changes in the slopes of the pressure dependences of volume and selected cell parameters have been observed for yttrium-containing salts at 3.5 GPa. This may be related to the re-distribution of water molecules within the crystal structure. Y2(C2O4)3·10H2O undergoes a partial dehydration at 1 GPa, forming monoclinic Y2(C2O4)3·6H2O as single-crystalline inclusions in the original phase.

KW - dehydration

KW - high pressures

KW - isostructural salt hydrates

KW - ELEMENTS

KW - YTTRIUM

UR - http://www.scopus.com/inward/record.url?scp=85032960561&partnerID=8YFLogxK

U2 - 10.1515/zkri-2016-2038

DO - 10.1515/zkri-2016-2038

M3 - Article

AN - SCOPUS:85032960561

VL - 232

SP - 751

EP - 757

JO - Zeitschrift fur Kristallographie - Crystalline Materials

JF - Zeitschrift fur Kristallographie - Crystalline Materials

SN - 2194-4946

IS - 11

ER -