High-Pressure Preparation, Crystal Structure, and Properties of RE4B6O15 (RE = Dy, Ho) with an Extension of the “Fundamental Building Block”-Descriptors

High-pressure/high-temperature conditions of 8 GPa and 1000°C were used to synthesizethe new rare earth oxoborates RE4B6O15 (RE = Dy, Ho) in a Walker-type multianvil apparatus.The single crystal X-ray structure determination of Ho4B6O15 revealed the followingdata: C2/c, a = 1164.1(1), b = 436.7(1), c = 1882.5(1) pm, β = 96.71(1)°, Z = 4, R1 = 0.0291, wR2 = 0.0505 (all data). The two isotypic compounds exhibit a new structure type built up from corrugated layers of BO4 tetrahedra. In contrast to all known oxoborates the linkingof the BO4 tetrahedra is partially realized via common edges. Regarding the “fundamentalbuilding block”-concept, we introduce a new descriptor “” for edge-sharing BO4 tetrahedra.Temperature-resolved in situ powder diffraction measurements and IR/Raman-spectroscopicinvestigations on Dy4B6O15 are also reported.

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Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

10.26434/chemrxiv.11345063.v2 ◽

2020 ◽

Author(s):

Keishiro Yamashita ◽

Kazuki Komatsu ◽

Hiroyuki Kagi

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Crystal Growth ◽

Single Crystal ◽

Room Temperature ◽

Growth Technique ◽

Salt Hydrate ◽

X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl2·7H2O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

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High Pressure Earth Science. Determination of the Phase Boundaries of Mantle Minerals using in situ X-ray Diffraction Technique.

The Review of High Pressure Science and Technology ◽

10.4131/jshpreview.9.34 ◽

1999 ◽

Vol 9 (1) ◽

pp. 34-42

Author(s):

Norimasa NISHIYAMA ◽

Tetsuo IRIFUNE

Keyword(s):

High Pressure ◽

Earth Science ◽

X Ray Diffraction ◽

Phase Boundaries ◽

Mantle Minerals ◽

X Ray

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Ce2B8O15: High-pressure synthesis and crystal structure determination of a rare-earth polyborate exhibiting a new “Fundamental Building Block”

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.2013.1653 ◽

2013 ◽

Vol 228 (9) ◽

Author(s):

Matthias Glätzle ◽

Gunter Heymann ◽

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Rare Earth ◽

Structure Determination ◽

Building Block ◽

Synthesis And Crystal Structure ◽

High Pressure Synthesis ◽

Fundamental Building Block ◽

Pressure Synthesis

AbstractThe new cerium polyborate Ce

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High-Pressure Preparation, Crystal Structure, and Properties of Ln4B6O15 (Ln: Dy, Ho) with and Extension of the “Fundamental Building Block”-Descriptors.

ChemInform ◽

10.1002/chin.200329005 ◽

2003 ◽

Vol 34 (29) ◽

Author(s):

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Building Block ◽

Structure And Properties ◽

Fundamental Building Block

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Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

10.26434/chemrxiv.11345063.v1 ◽

2019 ◽

Author(s):

Keishiro Yamashita ◽

Kazuki Komatsu ◽

Hiroyuki Kagi

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Crystal Growth ◽

Single Crystal ◽

Room Temperature ◽

Growth Technique ◽

Salt Hydrate ◽

X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl2·7H2O at 2.51 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

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The untypical high-pressure Zintl phase SrGe6

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0197 ◽

2020 ◽

Vol 75 (1-2) ◽

pp. 209-216 ◽

Cited By ~ 1

Author(s):

Ulrich Schwarz ◽

Rodrigo Castillo ◽

Julia M. Hübner ◽

Aron Wosylus ◽

Yurii Prots ◽

...

Keyword(s):

High Pressure ◽

Ambient Pressure ◽

Three Dimensional ◽

Structure Type ◽

Ambient Conditions ◽

X Ray Diffraction ◽

Quantum Chemical Analysis ◽

Electronic Density ◽

X Ray ◽

High Pressure High Temperature

AbstractThe binary strontium germanide SrGe6 was synthesized at high-pressure high-temperature conditions of approximately 10 GPa and typically 1400 K before quenching to ambient conditions. At ambient pressure, SrGe6 decomposes in a monotropic fashion at T = 680(10) K into SrGe2 and Ge, indicating its metastable character. Single-crystal X-ray diffraction data indicate that the compound SrGe6 adopts a new monoclinic structure type comprising a unique three-dimensional framework of germanium atoms with unusual cages hosting the strontium cations. Quantum chemical analysis of the chemical bonding shows that the framework consists of three- and four- bonded germanium atoms yielding the precise electron count Sr[(4bGe0]4[(3b)Ge−]2 in accordance with the 8 − N rule and the Zintl concept. Conflicting with that, a pseudo-gap in the electronic density of states appears clearly below the Fermi level, and elaborate bonding analysis reveals additional Sr–Ge interactions in the concave coordination polyhedron of the strontium atoms.

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Crystal structure of RbBaVO4 and high-pressure modification of KCaVO4

Powder Diffraction ◽

10.1017/s0885715613001140 ◽

2013 ◽

Vol 28 (S2) ◽

pp. S65-S74 ◽

Cited By ~ 1

Author(s):

N.V. Tarakina ◽

A.P. Tyutyunnik ◽

T.V. Dyachkova ◽

L.L. Surat ◽

B.V. Slobodin ◽

...

Keyword(s):

High Pressure ◽

Unit Cell Volume ◽

Structure Type ◽

Powder Diffraction Data ◽

Conventional Solid State Reaction ◽

X Ray ◽

High Pressure High Temperature ◽

Coordination Spheres ◽

The Difference ◽

Dense State

The crystal structures of KCaVO4 and RbBaVO4, synthesized at high-pressure/high-temperature and by a conventional solid-state reaction, respectively, were determined using X-ray powder diffraction data. These compounds were found to have the β-K2SO4 structure type (space group Pnma, Z = 4) with parameters a = 7.2628(5) Å, b = 5.7258(4) Å, c = 9.6854(7) Å (KCaVO4), and a = 7.8887(1) Å, b = 5.9589(1) Å, c = 10.3958(2) Å (RbBaVO4). The unit cell volume of KCaVO4, 402.77(5) Å3, is significantly lower than for the low-temperature modification reported previously, 436.2 Å3. The difference can be explained by a pressure-induced phase transition to a more dense state resulting from the rotation of tetrahedra and the exchange of oxygen atoms from the first and second coordination spheres for potassium and calcium atoms.

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