Barium bis[tetrafluoridobromate(III)]

Single crystals of barium bis[tetrafluoridobromate(III)], Ba[BrF4]2, were obtained in the form of tiny blocks. Crystal-structure refinement of Ba[BrF4]2 from single-crystal X-ray diffraction data confirmed the previous model obtained on the basis of powder data [Ivlev et al. (2014). Eur. J. Inorg. Chem. pp. 6261–6267], but with all atoms refined with anisotropic displacement parameters. The crystal structure consists of two symmetry-independent barium cations that are each coordinated by twelve fluorine atoms, forming edge-sharing polyhedra, and an almost square-planar [BrF4]− anion. The compound crystallizes in the Ba[AuF4]2 structure type.

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Redetermination of Sr2PdO3 from single-crystal X-ray data

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989018017176 ◽

2019 ◽

Vol 75 (1) ◽

pp. 30-32

Author(s):

Gohil S. Thakur ◽

Hans Reuter ◽

Claudia Felser ◽

Martin Jansen

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Diffraction Data ◽

Structure Refinement ◽

Structure Type ◽

X Ray Diffraction ◽

High Quality ◽

X Ray ◽

Cell Parameters ◽

Anisotropic Displacement Parameters

The crystal structure redetermination of Sr2PdO3 (distrontium palladium trioxide) was carried out using high-quality single-crystal X-ray data. The Sr2PdO3 structure has been described previously in at least three reports [Wasel-Nielen & Hoppe (1970). Z. Anorg. Allg. Chem. 375, 209–213; Muller & Roy (1971). Adv. Chem. Ser. 98, 28–38; Nagata et al. (2002). J. Alloys Compd. 346, 50–56], all based on powder X-ray diffraction data. The current structure refinement of Sr2PdO3, as compared to previous powder data refinements, leads to more precise cell parameters and fractional coordinates, together with anisotropic displacement parameters for all sites. The compound is confirmed to have the orthorhombic Sr2CuO3 structure type (space group Immm) as reported previously. The structure consists of infinite chains of corner-sharing PdO4 plaquettes interspersed by SrII atoms. A brief comparison of Sr2PdO3 with the related K2NiF4 structure type is given.

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Rubidium tetrafluoridobromate(III): redetermination of the crystal structure from single-crystal X-ray diffraction data

IUCrData ◽

10.1107/s2414314619015955 ◽

2019 ◽

Vol 4 (11) ◽

Author(s):

Artem V. Malin ◽

Sergei I. Ivlev ◽

Roman V. Ostvald ◽

Florian Kraus

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

Structure Type ◽

X Ray Diffraction ◽

X Ray ◽

Square Planar ◽

Atomic Coordinates

Single crystals of rubidium tetrafluoridobromate(III), RbBrF4, were grown by melting and recrystallizing RbBrF4 from its melt. This is the first determination of the crystal structure of RbBrF4 using single-crystal X-ray diffraction data. We confirmed that the structure contains square-planar [BrF4]− anions and rubidium cations that are coordinated by F atoms in a square-antiprismatic manner. The compound crystallizes in the KBrF4 structure type. Atomic coordinates and bond lengths and angles were determined with higher precision than in a previous report based on powder X-ray diffraction data [Ivlev et al. (2015). Z. Anorg. Allg. Chem. 641, 2593–2598].

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Redetermination of the crystal structure of K[BrF4] from single-crystal X-ray diffraction data

IUCrData ◽

10.1107/s2414314618006466 ◽

2018 ◽

Vol 3 (5) ◽

Cited By ~ 4

Author(s):

Sergei I. Ivlev ◽

Florian Kraus

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

Potassium Cation ◽

X Ray Diffraction ◽

X Ray ◽

Square Planar ◽

Anisotropic Displacement Parameters ◽

Current Report

Single crystals of K[BrF4], potassium tetrafluoridobromate(III), were grown from a solution of KHF2 in bromine trifluoride. The current report is the first refinement of the crystal structure of K[BrF4] using single-crystal X-ray diffraction data. In comparison with previous refinements from powder data, the fractional coordinates of the F atom were determined with higher precision, and anisotropic displacement parameters were refined for all atoms. The structure contains square-planar [BrF4]− anions. The coordination polyhedron of the potassium cation is a square antiprism.

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Redetermination of the crystal structure of RhPb2 from single-crystal X-ray diffraction data, revealing a rhodium deficiency

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989021012275 ◽

2021 ◽

Vol 77 (12) ◽

Author(s):

Takashi Mochiku ◽

Yoshitaka Matsushita ◽

Nikola Subotić ◽

Takanari Kashiwagi ◽

Kazuo Kadowaki

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Diffraction Data ◽

Structure Type ◽

Site Symmetry ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters ◽

Anisotropic Displacement Parameters ◽

Slight Deficiency

RhPb2 (rhodium dilead) is a superconductor crystallizing in the CuAl2 structure type (space group I4/mcm). The Rh and Pb atoms are located at the 4a (site symmetry 422) and 8h (m.2m) sites, respectively. The crystal structure is composed of [RhPb8] antiprisms, which share their square faces along the c axis and the edges in the direction perpendicular to the c axis. We have succeeded in growing single crystals of RhPb2 and have re-determined the crystal structure on basis of single-crystal X-ray diffraction data. In comparison with the previous structure studies using powder X-ray diffraction data [Wallbaum (1943). Z. Metallkd. 35, 218–221; Havinga et al. (1972). J. Less-Common Met. 27, 169–186], the current structure analysis of RhPb2 leads to more precise unit-cell parameters and fractional coordinates, together with anisotropic displacement parameters for the two atoms. In addition and likewise different from the previous studies, we have found a slight deficiency of Rh in RhPb2, leading to a refined formula of Rh0.950 (9)Pb2.

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Diterbium heptanickel: a crystal structure redetermination

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536814015384 ◽

2014 ◽

Vol 70 (8) ◽

pp. i42-i42

Author(s):

Volodymyr Levytskyy ◽

Volodymyr Babizhetskyy ◽

Bohdan Kotur ◽

Volodymyr Smetana

Keyword(s):

Crystal Structure ◽

Diffraction Data ◽

Title Compound ◽

Stoichiometric Composition ◽

Structure Type ◽

Asymmetric Unit ◽

X Ray Diffraction ◽

Coordination Polyhedra ◽

X Ray ◽

Anisotropic Displacement Parameters

The crystal structure of the title compound, Tb2Ni7, was redetermined from single-crystal X-ray diffraction data. In comparison with previous studies based on powder X-ray diffraction data [Lemaireet al.(1967).C. R. Acad. Sci. Ser. B,265, 1280–1282; Lemaire & Paccard (1969).Bull. Soc. Fr. Mineral. Cristallogr.92, 9–16; Buschow & van der Goot (1970).J. Less-Common Met.22, 419–428], the present redetermination affords refined coordinates and anisotropic displacement parameters for all atoms. A partial occupation for one Tb atom results in the non-stoichiometric composition Tb1.962 (4)Ni7. The title compound adopts the Ce2Ni7structure type and can also be derived from the CaCu5structure type as an intergrowth structure. The asymmetric unit contains two Tb sites (both site symmetries 3m.) and five Ni sites (.m.,mm2, 3m., 3m., -3m.). The two different coordination polyhedra of Tb are a Frank–Kasper polyhedron formed by four Tb and 12 Ni atoms and a pseudo Frank–Kasper polyhedron formed by two Tb and 18 Ni atoms. The four different coordination polyhedra of Ni are Frank–Kasper icosahedra formed by five Tb and seven Ni atoms, four Tb and eight Ni atoms, three Tb and nine Ni atoms, and six Tb and six Ni atoms, respectively.

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Redetermination of Mg2B25 based on single-crystal X-ray data

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536812023768 ◽

2012 ◽

Vol 68 (6) ◽

pp. i50-i50 ◽

Cited By ~ 2

Author(s):

Luca Bindi ◽

Alessandro Figini Albisetti ◽

Giovanni Giunchi ◽

Luciana Malpezzi ◽

Norberto Masciocchi

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Diffraction Data ◽

Structural Model ◽

Structure Type ◽

Site Symmetry ◽

Metal Boride ◽

X Ray Diffraction ◽

X Ray ◽

Anisotropic Displacement Parameters

The crystal structure of Mg2B25, dimagnesium pentaeicosaboride, was reexamined from single-crystal X-ray diffraction data. The structural model previously reported on the basis of powder X-ray diffraction data [Giunchi et al. (2006). Solid State Sci. 8, 1202–1208] has been confirmed, although a much higher precision refinement was achieved, leading to much smaller standard uncertainties on bond lengths and refined occupancy factors. Moreover, all atoms were refined with anisotropic displacement parameters. Mg2B25 crystallizes in the β-boron structure type and is isostructural with other rhombohedral compounds of the boron-rich metal boride family. Magnesium atoms are found in interstitial sites on special positions (two with site symmetry .m, one with .2 and one with 3m), all with partial occupancies.

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Synthesis and Rietveld crystal structure refinement of mackinawite, tetragonal FeS

Mineralogical Magazine ◽

10.1180/minmag.1995.059.397.10 ◽

1995 ◽

Vol 59 (397) ◽

pp. 677-683 ◽

Cited By ~ 154

Author(s):

A. R. Lennie ◽

S. A. T. Redfern ◽

P. F. Schofield ◽

D. J. Vaughan

Keyword(s):

Crystal Structure ◽

Diffraction Data ◽

Structure Refinement ◽

X Rays ◽

Crystal Structure Refinement ◽

Powder Diffraction Data ◽

X Ray Diffraction ◽

Data Set ◽

X Ray ◽

Cell Parameters

AbstractMackinawite, tetragonal FeS, has been synthesised by reacting iron with Na2S solutions. A Rietveld structure refinement of X-ray powder diffraction data, recorded using X-rays monochromated from synchrotron radiation with a wavelength of 0.6023 Å, has been performed. The structure has been refined in the tetragonal space group, P4/nmm, and has the following cell parameters: a = 3.6735(4), c = 5.0328(7) Å, V = 67.914(24) Å3. Our refinement shows that the FeS4 tetrahedron in mackinawite is almost perfectly regular, with a much smaller distortion than has been previously reported. An improved X-ray diffraction data set is provided.

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Redetermination of the crystal structure of β-zinc molybdate from single-crystal X-ray diffraction data

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s205698901501186x ◽

2015 ◽

Vol 71 (7) ◽

pp. i6-i7 ◽

Cited By ~ 1

Author(s):

Olfa Mtioui-Sghaier ◽

Rafael Mendoza-Meroño ◽

Lilia Ktari ◽

Mohamed Dammak ◽

Santiago García-Granda

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Diffraction Data ◽

Point Group ◽

Structure Type ◽

Group Symmetry ◽

X Ray Diffraction ◽

X Ray ◽

Bond Lengths ◽

Anisotropic Displacement Parameters

The crystal structure of the β-polymorph of ZnMoO4was re-determined on the basis of single-crystal X-ray diffraction data. In comparison with previous powder X-ray diffraction studies [Katikaneani & Arunachalam (2005).Eur. J. Inorg. Chem. pp. 3080–3087; Cavalcanteet al.(2013).Polyhedron,54, 13–25], all atoms were refined with anisotropic displacement parameters, leading to a higher precision with respect to bond lengths and angles. β-ZnMoO4adopts the wolframite structure type and is composed of distorted ZnO6and MoO6octahedra, both with point group symmetry 2. The distortion of the octahedra is reflected by variation of bond lengths and angles from 2.002 (3)–2.274 (4) Å, 80.63 (11)–108.8 (2)° for equatorial and 158.4 (2)– 162.81 (14)° for axial angles (ZnO6), and of 1.769 (3)–2.171 (3) Å, 73.39 (16)–104.7 (2), 150.8 (2)–164.89 (15)° (MoO6), respectively. In the crystal structure, the same type ofMO6octahedra share edges to built up zigzag chains extending parallel to [001]. The two types of chains are condensed by common vertices into a framework structure. The crystal structure can alternatively be described as derived from a distorted hexagonally closed packed arrangement of the O atoms, with Zn and Mo in half of the octahedral voids.

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