High-pressure synthesis of REB5O8(OH)2 (RE = Ho, Er, Tm)

AbstractThe rare earth oxoborates REB5O8(OH)2 (RE = Ho, Er, Tm) were synthesized in a Walker-type multianvil apparatus at a pressure of 2.5 GPa and a temperature of 673 K. Single-crystal X-ray diffraction data provided the basis for the structure solution and refinement. The compounds crystallize in the monoclinic space group C2 (no. 5) and are composed of a layer-like structure containing dreier and sechser rings of corner sharing [BO4]5− tetrahedra. The rare earth metal cations are coordinated between two adjacent sechser rings. Further characterization was performed utilizing IR spectroscopy.

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High-pressure synthesis and characterization of the non-centrosymmetric scandium borate ScB6O9(OH)3

Zeitschrift für Naturforschung B ◽

10.1515/znb-2020-0070 ◽

2020 ◽

Vol 75 (6-7) ◽

pp. 597-603

Author(s):

Birgit Fuchs ◽

Hubert Huppertz

Keyword(s):

High Pressure ◽

High Temperature ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

X Ray ◽

High Pressure High Temperature ◽

Structure Solution ◽

Temperature Experiment ◽

Pressure Synthesis

AbstractThe non-centrosymmetric scandium borate ScB6O9(OH)3 was obtained through a high-pressure/high-temperature experiment at 6 GPa and 1473 K. Single-crystal X-ray diffraction revealed that the structure is isotypic to InB6O9(OH)3 containing borate triple layers separated by scandium layers. The compound crystallizes in the space group Fdd2 with the lattice parameters a = 38.935(4), b = 4.4136(4), and c = 7.6342(6) Å. Powder X-ray diffraction and vibrational spectroscopy were used to further characterize the compound and verify the proposed structure solution.

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High-pressure synthesis and crystal structure of the samarium meta-oxoborate γ-Sm(BO2)3

Zeitschrift für Naturforschung B ◽

10.1515/znb-2020-0045 ◽

2020 ◽

Vol 75 (6-7) ◽

pp. 589-595

Author(s):

Birgit Fuchs ◽

Robert O. Kindler ◽

Gunter Heymann ◽

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Rare Earth ◽

Earth Element ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

Synthesis And Crystal Structure ◽

X Ray ◽

High Pressure High Temperature ◽

Pressure Synthesis

Abstractγ-Sm(BO2)3 was obtained via a high-pressure/high-temperature approach in a multi-anvil apparatus at 10 GPa and 1673 K. It crystallizes in the orthorhombic space group Pca21 (no. 29) with the lattice parameters a = 18.3088(8), b = 4.4181(2), and c = 4.2551(2) Å. The compound was analysed by means of X-ray diffraction and vibrational spectroscopy. The structure is isotypic to that of the already known meta-oxoborates γ-RE(BO2)3 (RE = La−Nd) and built up of a highly condensed borate framework containing three-, four-, six-, and ten-membered rings. Next to neodymium, samarium represents the second rare earth element that forms the α-, β-, and γ-modification of the four known rare earth meta-oxoborate structure types.

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High-pressure synthesis and crystal structure of α-Y2B4O9

Zeitschrift für Naturforschung B ◽

10.1515/znb-2017-0150 ◽

2017 ◽

Vol 72 (12) ◽

pp. 977-982 ◽

Cited By ~ 4

Author(s):

Martin K. Schmitt ◽

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Synthesis And Crystal Structure ◽

X Ray ◽

High Pressure High Temperature ◽

Temperature Experiment ◽

Pressure Synthesis ◽

Ir And Raman

Abstractα-Y2B4O9 was synthesized in a high-pressure/high-temperature experiment at 12.3 GPa/1020°C. The crystal structure has been determined via single-crystal X-ray diffraction. α-Y2B4O9 is isotypic to the lanthanide borates α-Ln2B4O9 (Ln=Sm–Ho) and crystallizes in the monoclinic space group C2/c (no. 15) with the following lattice parameters: a=25.084(2), b=4.3913(2), c=24.726(2) Å, and β=99.97(1)°. The compound was further characterized via X-ray powder diffraction as well as IR and Raman spectroscopy.

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High-pressure synthesis and crystal structure of the mixed-cation borate Ga4In4B15O33(OH)3

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0014 ◽

2019 ◽

Vol 74 (4) ◽

pp. 357-363

Author(s):

Daniela Vitzthum ◽

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

High Temperature ◽

Diffraction Data ◽

X Ray Diffraction ◽

Synthesis And Crystal Structure ◽

X Ray ◽

Mixed Cation ◽

High Pressure High Temperature ◽

Pressure Synthesis

AbstractThe mixed cation triel borate Ga4In4B15O33(OH)3 was synthesized in a Walker-type multianvil apparatus at high-pressure/high-temperature conditions of 12.5 GPa and 1300°C. Although the product could not be reproduced in further experiments, its crystal structure could be reliably determined via single-crystal X-ray diffraction data. Ga4In4B15O33(OH)3 crystallizes in the tetragonal space group I41/a (origin choice 2) with the lattice parameters a = 11.382(2), c = 15.244(2) Å, and V = 1974.9(4) Å3. The structure of the quaternary triel borate consists of a complex network of BO4 tetrahedra, edge-sharing InO6 octahedra in dinuclear units, and very dense edge-sharing GaO6 octahedra in tetranuclear units.

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High Pressure X-ray Diffraction as a Tool for Designing Doped Ceria Thin Films Electrolytes

Coatings ◽

10.3390/coatings11060724 ◽

2021 ◽

Vol 11 (6) ◽

pp. 724

Author(s):

Sara Massardo ◽

Alessandro Cingolani ◽

Cristina Artini

Keyword(s):

Thin Films ◽

High Pressure ◽

Rare Earth ◽

Ionic Conductivity ◽

Bulk Material ◽

Threshold Temperature ◽

Doped Ceria ◽

X Ray Diffraction ◽

X Ray ◽

Rare Earth Doped

Rare earth-doped ceria thin films are currently thoroughly studied to be used in miniaturized solid oxide cells, memristive devices and gas sensors. The employment in such different application fields derives from the most remarkable property of this material, namely ionic conductivity, occurring through the mobility of oxygen ions above a certain threshold temperature. This feature is in turn limited by the association of defects, which hinders the movement of ions through the lattice. In addition to these issues, ionic conductivity in thin films is dominated by the presence of the film/substrate interface, where a strain can arise as a consequence of lattice mismatch. A tensile strain, in particular, when not released through the occurrence of dislocations, enhances ionic conduction through the reduction of activation energy. Within this complex framework, high pressure X-ray diffraction investigations performed on the bulk material are of great help in estimating the bulk modulus of the material, and hence its compressibility, namely its tolerance toward the application of a compressive/tensile stress. In this review, an overview is given about the correlation between structure and transport properties in rare earth-doped ceria films, and the role of high pressure X-ray diffraction studies in the selection of the most proper compositions for the design of thin films.

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X-Ray Diffraction Study of Rare Earth Epitaxial Structures Grown by MBE onto (111) GaAs

MRS Proceedings ◽

10.1557/proc-151-277 ◽

1989 ◽

Vol 151 ◽

Author(s):

W. R. Bennett ◽

R. F. C. Farrow ◽

S. S. P. Parkin ◽

E. E. Marinero

Keyword(s):

Rare Earth ◽

Molecular Beam Epitaxy ◽

Rare Earth Metal ◽

Molecular Beam ◽

Earth Metal ◽

Magnetic Ordering ◽

Metal Films ◽

X Ray Diffraction ◽

X Ray ◽

Strain Components

ABSTRACTWe report on the new epitaxial system LaF3/Er/Dy/Er/LaF3/GaAs (111) grown by molecular beam epitaxy. X-ray diffraction studies have been used to determine the epitaxial relationships between the rare earths, the LaF3 and the substrate. Further studies of symmetric and asymmetric reflections yielded the in-plane and perpendicular strain components of the rare earth layers. Such systems may be used to probe the effects of magnetoelastic interactions and dimensionality on magnetic ordering in rare earth metal films and multilayers.

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Single-crystal Data of Ternary Germanides RE2Nb3Ge4 (RE = Sc, Y, Gd–Er, Lu) and Sc2Ta3Ge4 with Ordered Sm5Ge4-type Structure

Zeitschrift für Naturforschung B ◽

10.5560/znb.2013-3041 ◽

2013 ◽

Vol 68 (5-6) ◽

pp. 625-634 ◽

Cited By ~ 2

Author(s):

Bastian Reker ◽

Samir F. Matar ◽

Ute Ch. Rodewald ◽

Rolf-Dieter Hoffmann ◽

Rainer Pöttgen

Keyword(s):

Rare Earth ◽

Single Crystal ◽

Coordination Number ◽

Electronic Structure Calculations ◽

Crystal Data ◽

X Ray Diffraction ◽

X Ray ◽

Arc Melting ◽

Structure Calculations ◽

The Rare Earth

Small single crystals of the Sm5Ge4-type (space group Pnma) germanides RE2Nb3Ge4 (RE = Sc, Y, Gd-Er, Lu) and Sc2Ta3Ge4 were synthesized by arc-melting of the respective elements. The samples were characterized by powder and single-crystal X-ray diffraction. In all structures, except for Sc2.04Nb2.96Ge4 and Sc2.19Ta2.81Ge4, the rare earth and niobium atoms show full ordering on the three crystallographically independent samarium sites of the Sm5Ge4 type. Two sites with coordination number 6 are occupied by niobium, while the slightly larger site with coordination number 7 is filled with the rare earth element. Small homogeneity ranges with RE=Nb and RE=Ta mixing can be expected for all compounds. The ordered substitution of two rare earth sites by niobium or tantalum has drastic effects on the coordination number and chemical bonding. This was studied for the pair Y5Ge4/Y2Nb3Ge4. Electronic structure calculations show larger charge transfer from yttrium to germanium for Y5Ge4, contrary to Y2Nb3Ge4 which shows stronger covalent bonding due to the presence of Nb replacing Y at two sites

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Synthesis and crystal structure of the rare earth borogermanate EuGeBO5

Zeitschrift für Naturforschung B ◽

10.1515/znb-2016-0107 ◽

2017 ◽

Vol 72 (2) ◽

pp. 95-99 ◽

Cited By ~ 2

Author(s):

Yang Chi ◽

Yan Zhuang ◽

Sheng-Ping Guo

Keyword(s):

Crystal Structure ◽

Rare Earth ◽

Earth Metal ◽

Monoclinic Space Group ◽

Unit Cell Parameters ◽

Synthesis And Crystal Structure ◽

Cell Parameters ◽

Type Layer ◽

Related Compounds ◽

The Rare Earth

AbstractThe synthesis and crystal structure of the rare earth borogermanate EuGeBO5 are reported. It is synthesized by high-temperature solid-state reaction and crystallizes in the monoclinic space group P21/c (no. 14) with the unit cell parameters a=4.8860(5), b=7.5229(8), c=9.9587(10) Å, and β=91.709(3)°. Its crystal structure features a polyanion-type layer (GeBO5)3− constructed by BO4 and GeO4 tetrahedra connected alternatingly. Eu3+ ions are located in cavities and are coordinated by eight O atoms. Various structures of the related compounds REMM′O5 (RE=rare earth metal; M=Si, Ge, and Sn; M′=B, Al, and Ga) are also discussed.

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