scholarly journals Crystal structures of Ca4+x Y3–x Si7O15+x N5–x (0 ≤ x ≤ 1) comprising of an isolated [Si7(O,N)19] unit

2019 ◽  
Vol 75 (2) ◽  
pp. 260-263
Author(s):  
Makoto Kobayashi ◽  
Takuya Yasunaga ◽  
Hideki Kato ◽  
Kotaro Fujii ◽  
Masatomo Yashima ◽  
...  
Keyword(s):  
Layer Structure ◽  
Point Group ◽  
Solid State Reaction Method ◽  
Group Symmetry ◽  
Site Symmetry ◽  
Point Group Symmetry ◽  
Solid Solution Series ◽  
Reaction Method ◽  
X Ray ◽  
Group Type

Single crystals of the solid solution series Ca4+x Y3–x Si7O15+x N5–x were obtained by a solid-state reaction method using a flux for x = 0, 0.5 and 1, resulting in Ca4Y3Si7O15N5 (tetracalcium triyttrium heptasilicon oxynitride), Ca4.5Y2.5Si7O15.5N4.5 and Ca5Y2Si7O16N4 (pentacalcium diyttrium heptasilicon oxynitride). Single-crystal X-ray analysis revealed that the three compounds are isotypic and belong to space-group type P63/m. Ca2+ and Y3+ cations are distributed over two crystallographic sites (site symmetry \overline{3}.. and 1) in a disordered manner. The corresponding (Ca,Y)-centred polyhedra are connected by edge-sharing, resulting in the formation of a layer structure extending parallel to (001). Three [Si(O,N)]4 tetrahedra (two with point group symmetry m.., one with 3.. and half-occupancy) are condensed into an isolated [Si7(O,N)19] unit, in which an [Si(O,N)]4 tetrahedron is located at the center of a 12-membered oxynitride ring with composition [Si6O15N3]. The present compounds are the first to have such an [Si7(O,N)19] unit in their structures.

scholarly journals Crystal structure of Ti8Bi9O0.25 containing interstitial oxygen atoms

2018 ◽  
Vol 74 (9) ◽  
pp. 1366-1368
Author(s):  
Hisanori Yamane ◽  
Keita Hiraka
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Bismuth Oxide ◽  
Point Group ◽  
Group Symmetry ◽  
Interstitial Oxygen ◽  
Point Group Symmetry ◽  
X Ray ◽  
Group Type ◽  
Oxygen Site

Single crystals of Ti8Bi9O0.25, titanium bismuth oxide (8/9/0.25), were obtained from a sample prepared by heating a mixture of Ti, TiO2 and Bi powders in an Ar atmosphere. Single-crystal X-ray analysis revealed that the introduction of O atoms into the structure of Ti8Bi9 retains the space-group type P4/nmm. The oxygen site is located within a Ti4 tetrahedron (point group symmetry \overline{4}m2) that is vacant in the Ti8Bi9 crystal structure. The occupancy of this site is 0.25 (4), and the O—Ti distance is 1.8824 (11) Å.

scholarly journals Synthesis and crystal structure of cerium(IV) bis(phosphite)

2017 ◽  
Vol 73 (9) ◽  
pp. 1290-1293
Author(s):  
Stefano H. Byer ◽  
Eric M. Villa
Keyword(s):  
Crystal Structure ◽  
Layered Structure ◽  
Point Group ◽  
Group Symmetry ◽  
Site Symmetry ◽  
Point Group Symmetry ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Structural Details

The structure of cerium(IV) bis(phosphite), Ce(HPO3)2, has been solved by single-crystal X-ray diffraction and has trigonal (P-3m1) symmetry. The cerium(IV) cation exhibits site symmetry -3m. and is octahedrally coordinated by O atoms of the phosphite ligands (point group symmetry 3m.). The highly symmetrical compound has a layered structure parallel to theabplane, and is closely related to zirconium(IV) bis(phosphite) solvedviapowder X-ray diffraction with trigonal (P-3 symmetry. Structural details of the two compounds are comparatively discussed.

scholarly journals Crystal structure of langbeinite-related Rb0.743K0.845Co0.293Ti1.707(PO4)3

2015 ◽  
Vol 71 (3) ◽  
pp. 251-253 ◽  
Author(s):  
Nataliia Yu. Strutynska ◽  
Marina A. Bondarenko ◽  
Ivan V. Ogorodnyk ◽  
Vyacheslav N. Baumer ◽  
Nikolay S. Slobodyanik
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Point Group ◽  
Three Dimensional ◽  
Type Structure ◽  
Group Symmetry ◽  
Site Symmetry ◽  
Point Group Symmetry ◽  
Crystallization Method ◽  
Temperature Crystallization

Potassium rubidium cobalt(II)/titanium(IV) tris(orthophosphate), Rb0.743K0.845Co0.293Ti1.707(PO4)3, has been obtained using a high-temperature crystallization method. The obtained compound has a langbeinite-type structure. The three-dimensional framework is built up from mixed-occupied (Co/TiIV)O6octahedra (point group symmetry .3.) and PO4tetrahedra. The K+and Rb+cations are statistically distributed over two distinct sites (both with site symmetry .3.) in the large cavities of the framework. They are surrounded by 12 O atoms.

scholarly journals Crystal structures of two alkaline earth (M= Ba and Sr) dimanganese(II) iron(III) tris(orthophosphates)

2017 ◽  
Vol 73 (5) ◽  
pp. 767-770
Author(s):  
Ghaleb Alhakmi ◽  
Abderrazzak Assani ◽  
Mohamed Saadi ◽  
Lahcen El Ammari
Keyword(s):  
Crystal Structures ◽  
Alkaline Earth ◽  
Point Group ◽  
Three Dimensional ◽  
Group Symmetry ◽  
Solid State Reactions ◽  
Site Symmetry ◽  
Orthorhombic System ◽  
Group Type ◽  
Alkaline Earth Cations

Two new orthophosphates, BaMn2Fe(PO4)3[barium dimanganese(II) iron(III) tris(orthophosphate)] and SrMn2Fe(PO4)3[strontium dimanganese(II) iron(III) tris(orthophosphate)], were synthesized by solid-state reactions. They are isotypic and crystallize in the orthorhombic system with space group typePbcn. Their crystal structures comprise infinite zigzag chains of edge-sharing FeO6octahedra (point group symmetry .2.) and Mn2O10double octahedra running parallel to [001], linked by two types of PO4tetrahedra. The so-formed three-dimensional framework delineates channels running along [001], in which the alkaline earth cations (site symmetry .2.) are located within a neighbourhood of eight O atoms.

scholarly journals Crystal structure of post-perovskite-type CaIrO3reinvestigated: new insights into atomic thermal vibration behaviors

2015 ◽  
Vol 71 (9) ◽  
pp. 1109-1113
Author(s):  
Akihiko Nakatsuka ◽  
Kazumasa Sugiyama ◽  
Akira Yoneda ◽  
Keiko Fujiwara ◽  
Akira Yoshiasa
Keyword(s):  
Crystal Structure ◽  
Atmospheric Pressure ◽  
Structure Refinement ◽  
Point Group ◽  
Group Symmetry ◽  
Point Group Symmetry ◽  
X Ray ◽  
Thermal Vibrations ◽  
Perovskite Type ◽  
Shared Edge

Single crystals of the title compound, the post-perovskite-type CaIrO3[calcium iridium(IV) trioxide], have been grown from a CaCl2flux at atmospheric pressure. The crystal structure consists of an alternate stacking of IrO6octahedral layers and CaO8hendecahedral layers along [010]. Chains formed by edge-sharing of IrO6octahedra (point-group symmetry 2/m..) run along [100] and are interconnected along [001] by sharing apical O atoms to build up the IrO6octahedral layers. Chains formed by face-sharing of CaO8hendecahedra (point-group symmetrym2m) run along [100] and are interconnected along [001] by edge-sharing to build up the CaO8hendecahedral layers. The IrO6octahedral layers and CaO8hendecahedral layers are interconnected by sharing edges. The present structure refinement using a high-power X-ray source confirms the atomic positions determined by Hiraiet al.(2009) [Z. Kristallogr.224, 345–350], who had revised our previous report [Sugaharaet al.(2008).Am. Mineral.93, 1148–1152]. However, the displacement ellipsoids of the Ir and Ca atoms based on the present refinement can be approximated as uniaxial ellipsoids elongating along [100], unlike those reported by Hiraiet al.(2009). This suggests that the thermal vibrations of the Ir and Ca atoms are mutually suppressed towards the Ir...Ca direction across the shared edge because of the dominant repulsion between the two atoms.

scholarly journals Redetermination of the crystal structure of caesium tetrafluoridobromate(III) from single-crystal X-ray diffraction data

IUCrData ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Artem V. Malin ◽  
Sergei I. Ivlev ◽  
Roman V. Ostvald ◽  
Florian Kraus
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Diffraction Data ◽  
Point Group ◽  
Group Symmetry ◽  
Site Symmetry ◽  
X Ray Diffraction ◽  
Cation Site ◽  
X Ray ◽  
Square Planar

Caesium tetrafluoridobromate(III), CsBrF4, was crystallized in form of small blocks by melting and recrystallization. The crystal structure of CsBrF4 was redetermined from single-crystal X-ray diffraction data. In comparison with a previous study based on powder X-ray diffraction data [Ivlev et al. (2013). Z. Anorg. Allg. Chem. 639, 2846–2850], bond lengths and angles were determined with higher precision, and all atoms were refined with anisotropic displacement parameters. It was confirmed that the structure of CsBrF4 contains two square-planar [BrF4]− anions each with point group symmetry mmm, and a caesium cation (site symmetry mm2) that is coordinated by twelve fluorine atoms, forming an anticuboctahedron. CsBrF4 is isotypic with CsAuF4.

scholarly journals Crystal structure of alluaudite-type NaMg3(HPO4)2(PO4)

2015 ◽  
Vol 71 (7) ◽  
pp. 813-815 ◽  
Author(s):  
Ahmed Ould Saleck ◽  
Abderrazzak Assani ◽  
Mohamed Saadi ◽  
Cyrille Mercier ◽  
Claudine Follet ◽  
...  
Keyword(s):  
Point Group ◽  
Three Dimensional ◽  
The Other ◽  
Group Symmetry ◽  
Strong Hydrogen Bond ◽  
Site Symmetry ◽  
Point Group Symmetry ◽  
Hydrogen Phosphate ◽  
Hydrothermal Conditions ◽  
Different Types

The title compound, sodium trimagnesium bis(hydrogen phosphate) phosphate, was obtained under hydrothermal conditions. In the crystal, two types of [MgO6] octahedra, one with point group symmetry 2, share edges to build chains extending parallel to [10-1]. These chains are linked together by two kinds of phosphate tetrahedra, HPO4and PO4, the latter with point group symmetry 2. The three-dimensional framework delimits two different types of channels extending along [001]. One channel hosts the Na+cations (site symmetry 2) surrounded by eight O atoms, with Na—O bond lengths varying between 2.2974 (13) and 2.922 (2) Å. The OH group of the HPO4tetrahedron points into the other type of channel and exhibits a strong hydrogen bond to an O atom of the PO4tetrahedron on the opposite side.

scholarly journals Dimanganese(II) hydroxide vanadate, Mn2(OH)[VO4]

2014 ◽  
Vol 70 (7) ◽  
pp. i33-i33 ◽  
Author(s):  
Kewen Sun ◽  
Angela Möller
Keyword(s):  
Point Group ◽  
Three Dimensional ◽  
Group Symmetry ◽  
Site Symmetry ◽  
Point Group Symmetry ◽  
Distorted Octahedral Coordination ◽  
Trigonal Bipyramidal ◽  
Distorted Octahedral ◽  
Coordination Spheres ◽  
Distorted Trigonal Bipyramidal

Dimanganese(II) hydroxide vanadate was obtained from hydrothermal reactions. The crystal structure of the title compound is isotypic with that of Zn2(OH)[VO4]. Three crystallographically independent Mn2+ions are present, one (site symmetry .m.) with a distorted trigonal-bipyramidal and two (site symmetries .m. and 1) with distorted octahedral coordination spheres. These polyhedra are linked through common edges, forming a corrugated layer-type of structure extending parallel to (100). A three-dimensional framework resultsviaadditional Mn—O—V—O—Mn connectivities involving the two different tetrahedral [VO4] units (each with point-group symmetry .m.). O—H...O hydrogen bonds (one bifurcated) between the OH functions (both with point-group symmetry .m.) and the [VO4] units complete this arrangement.

scholarly journals Beiträge zur Chemie des Bors, 153 [1] Die Kristall- und Molekülstruktur eines 1.3.2-Dioxaborolan-2-yl-1.3.2-dioxaborolans

1984 ◽  
Vol 39 (11) ◽  
pp. 1463-1466 ◽  
Author(s):  
H. Nöth
Keyword(s):  
Point Group ◽  
Group Symmetry ◽  
Monoclinic Space Group ◽  
Point Group Symmetry ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography

Abstract The structure of the title com pound 5 has been investigated by X-ray crystallography in order to discern between two structural alternatives. 5 crystallizes in the monoclinic space group P21/c, and almost planar B-B bonded dioxaborolane rings are present in the molecule. 5 possesses a crystallographically imposed center of inversion, and approaches the point group symmetry D2h-

scholarly journals Structure cristalline de type alluaudite KNa5Mn3(MoO4)6

2015 ◽  
Vol 71 (1) ◽  
pp. 69-72 ◽  
Author(s):  
Chahira Bouzidi ◽  
Wafa Frigui ◽  
Mohamed Faouzi Zid
Keyword(s):  
Solid State ◽  
Point Group ◽  
Three Dimensional ◽  
Group Symmetry ◽  
Dimensional Structure ◽  
Site Symmetry ◽  
Structural Description ◽  
Point Group Symmetry ◽  
The Third ◽  
New Phase

The new phase potassium pentasodium trimanganese hexakis(molybdate), KNa5Mn3Mo6O24, has been synthesized using solid-state methods. The structure is composed ofM2O10(M= Mn, Na) dimers and MoO4tetrahedra (point group symmetry 2) sharing corners and forming layers parallel to (100), which are linkedviacommon corners of another type ofMO4tetrahedra, forming a three-dimensional structure with two types of large channels along [001] in which two types of Na+cations (one with site symmetry 2, one with -1) and K+cations (site symmetry 2, half-occupation) are located. Mn2+and the third type of Na+cations are located at the same siteMwith occupancies of 0.75 and 0.25, respectively. A comparative structural description is provided between the structure of the title compound and those of the related phases Cu1.35Fe3(PO4)3and NaAgFeMn2(PO4)3.

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