Darstellung und Kristallstruktur von Li2In und Li13In3 / Preparation and Crystal Structure of Li2ln and Li13ln3

1978 ◽  
Vol 33 (12) ◽  
pp. 1434-1437 ◽  
Author(s):  
Joachim Stöhr ◽  
Wiking Müller ◽  
Herbert Schäfer
Keyword(s):  
Crystal Structure ◽  
Structure Type ◽  
Space Group

Abstract Li2In crystallizes isotypic with Li2Ga, space group Cmcm-D2a17, a = 476.3(1), b = 1001.7(3) and c = 473.5(1) pm, the In-atoms build up zig-zag-chains. Li13In3 forms a new structure type, f.c.c., space group Fd 3m-Oh7, a = 1355.6(2) pm; it can be described as an ordered variant of the b.c.c. package with isolated In-atoms.

From Structure Topology to Chemical Composition. XXIX. Revision of the Crystal Structure of Perraultite, NaBaMn4Ti2(Si2O7)2O2(OH)2F, a Seidozerite-Supergroup TS-Block Mineral from the Oktyabr'skii Massif, Ukraine, and Discreditation of Surkhobite

2021 ◽  
Author(s):  
Elena Sokolova ◽  
Maxwell C. Day ◽  
Frank C. Hawthorne ◽  
Atali A. Agakhanov ◽  
Fernando Cámara ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Chemical Composition ◽  
Structure Type ◽  
Titanium Silicate ◽  
Space Group ◽  
Structure Topology ◽  
Ideal Composition ◽  
Using Data ◽  
Cation Sites ◽  
The Ideal

ABSTRACT The crystal structure of perraultite from the Oktyabr'skii massif, Donetsk region, Ukraine (bafertisite group, seidozerite supergroup), ideally NaBaMn4Ti2(Si2O7)2O2(OH)2F, Z = 4, was refined in space group C to R1 = 2.08% on the basis of 4839 unique reflections [Fo > 4σFo]; a = 10.741(6), b = 13.841(8), c = 11.079(6) Å, α = 108.174(6), β = 99.186(6), γ = 89.99(1)°, V = 1542.7(2.7) Å3. Refinement was done using data from a crystal with three twin domains which was part of a grain used for electron probe microanalysis. In the perraultite structure [structure type B1(BG), B – basic, BG – bafertisite group], there is one type of TS (Titanium-Silicate) block and one type of I (Intermediate) block; they alternate along c. The TS block consists of HOH sheets (H – heteropolyhedral, O – octahedral). In the O sheet, the ideal composition of the five [6]MO sites is Mn4 apfu. There is no order of Mn and Fe2+ in the O sheet. The MH octahedra and Si2O7 groups constitute the H sheet. The ideal composition of the two [6]MH sites is Ti2 apfu. The TS blocks link via common vertices of MH octahedra. The I block contains AP(1,2) and BP(1,2) cation sites. The AP(1) site is occupied by Ba and the AP(2) site by K > Ba; the ideal composition of the AP(1,2) sites is Ba apfu. The BP(1) and BP(2) sites are each occupied by Na > Ca; the ideal composition of the BP(1,2) sites is Na apfu. We compare perraultite and surkhobite based on the work of Sokolova et al. (2020) on the holotype sample of surkhobite: space group C , R1 = 2.85 %, a = 10.728(6), b = 13.845(8), c = 11.072(6) Å, α = 108.185(6), β = 99.219(5), γ = 90.001(8)°, V = 1540.0(2.5) Å3; new EPMA data. We show that (1) perraultite and surkhobite have identical chemical composition and ideal formula NaBaMn4Ti2(Si2O7)2O2(OH)2F; (2) perraultite and surkhobite are isostructural, with no order of Na and Ca at the BP(1,2) sites. Perraultite was described in 1991 and has precedence over surkhobite, which was redefined as “a Ca-ordered analogue of perraultite” in 2008. Surkhobite is not a valid mineral species and its discreditation was approved by CNMNC IMA (IMA 20-A).

scholarly journals Crystal structure of KNaCuP2O7, a new member of the diphosphate family

2018 ◽  
Vol 74 (2) ◽  
pp. 109-112 ◽  
Author(s):  
Ines Fitouri ◽  
Habib Boughzala
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Charge Distribution ◽  
Structural Model ◽  
Interlayer Space ◽  
Structure Type ◽  
Solid State Reactions ◽  
Space Group ◽  
Potassium Sodium ◽  
Bond Valence Sum

Potassium sodium copper(II) diphosphate(V), KNaCuP2O7, was synthesized by solid-state reactions. It crystallizes in the α-Na2CuP2O7 structure type in space group P21/n. In the crystal, CuO5 square-pyramids are linked to nearly eclipsed P2O7 groups by sharing corners to build up corrugated layers with composition [CuP2O7]2− that extend parallel to (010). The K+ and Na+ cations reside in the interlayer space and are connected to nine and seven O atoms, respectively. The structural model was validated by bond-valence-sum (BVS) and charge-distribution (CHARDI) analysis.

The crystal structure of trisodium hexachlororhodate (Na3RhCl6)

2018 ◽  
Vol 33 (1) ◽  
pp. 62-65
Author(s):  
Martin Etter
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Structure Type ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Commercially available trisodium hexachlororhodate (Na3RhCl6) was dehydrated and characterized by laboratory X-ray powder diffraction. The crystal structure is isostructural to the Na3CrCl6 structure type with space group P$\bar 31$c. Unit-cell parameters are a = 6.8116(1) Å, c = 11.9196(2) Å, V = 478.95(2) Å3, and Z = 2.

Crystal structure and powder data of davidite-type La2Ti10.27Ga9.63O38

1999 ◽  
Vol 14 (1) ◽  
pp. 36-41 ◽  
Author(s):  
A. Meden ◽  
D. Kolar ◽  
S. Škapin
Keyword(s):  
Crystal Structure ◽  
Rietveld Refinement ◽  
Structure Type ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Space Group ◽  
Cell Parameters

The structure type of La2Ti10.27Ga9.63O38 was revealed by a search-match using the PDF. A successful Rietveld refinement (Rp=8.9, Rwp=13.3, RB=4.20) confirmed the structure to be rhombohedral (space group R3¯, No. 148) with the refined unit cell parameters a=9.1878(1) Å, α=68.458(1)°, and V=646.374(1) Å3. The structure is compared to other compounds of the davidite type, and the observed and calculated powder data are given.

Zur Synthese und Kristallstruktur von Dibariumkaliumtrizinkborat Ba2KZn3(B3O6)(B6O13)/Synthesis and Crystal Structure of Di-barium Potassium Tri-zinc Borate Ba2KZn3(B3O6)(B6O13)

1996 ◽  
Vol 51 (3) ◽  
pp. 319-324 ◽  
Author(s):  
Silke Busche ◽  
Karsten Bluhm
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Structure Type ◽  
Lattice Parameters ◽  
Zinc Borate ◽  
Synthesis And Crystal Structure ◽  
Space Group ◽  
X Ray ◽  
Unknown Structure

Abstract Single crystals of the new compound Ba2KZn3(B3O6)(B6O13) were obtained by using a B2O3 flux technique; they crystallize in an as yet unknown structure type. X-ray investigations led to the space group Ci1-P1̄ (Nr.2) with lattice parameters a = 705.2(2), b = 712.5(2), c = 1880.3(6), a = 93.43(3)°, β = 90.72(2)°, γ = 119.57(2)°, Z = 2. The structure contains (B3O6)3--rings and a new discrete (B6O13)8- anion, which is composed of two BO4 and two B2O5 units. Zn2+ is tetrahedrally coordinated by oxygen and two out of three tenfold coordinated Ba-sites are statistically occupied by Ba2+ and K+.

Kristallstruktur von MnSO3 • H2O , eine fastsymmetrische schichtstruktur / Crystal structure of MnSO3 • H2O, a nearly symmetrical layer structure

1994 ◽  
Vol 49 (9) ◽  
pp. 1272-1276 ◽  
Author(s):  
Bernward Engelen
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Layer Structure ◽  
Structure Type ◽  
Space Group ◽  
Weak Hydrogen Bonds ◽  
Unknown Structure ◽  
Sulfite Ions

The crystal structure of MnSO3H2O , space group P21/n, Z = 4. Dx = 2.842(2) g · cm-3, a = 4.843(3), b = 12.807(6), c = 5.762(4) Å, β = 90.39(4)° has been determined. MnSO3·H2O crystallizes in a hitherto unknown structure type, which is closely related to that of orthorhombic MnSeO3· D2O. Coordination of Mn is octahedral involving O atom s from one water moleculeo and four different sulfite ions. The Mn-O distances range from 2.136(3) to 2.285(3)Å . The S-O distances are 1.552(3), 1.556(3) and 1.482(3)!Å. The MnO6 octahedra form layers parallel (010) by sharing four equatorial vertices. The layers are connected by weak hydrogen bonds and shifted laterally by 0.7 Å from the arrangement with m symmetry, found in MnSeO3·D2O. Due to this shift, the water molecule is asymmetrically bonded, as shown by both the O-H···O distances (2.967(4)-3.834(5)Å) and the OD stretching modes (2554 and 2576 cm-1) of partly deuterated samples

Crystal Structure of the New Compound NdFeSb3

2007 ◽  
Vol 353-358 ◽  
pp. 3043-3046 ◽  
Author(s):  
Ping Li Qin ◽  
Liang Qin Nong ◽  
Ji Liang Zhang ◽  
Hai Qing Qin ◽  
Jiang Ping Liao ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Rietveld Method ◽  
Structure Type ◽  
Lattice Parameters ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray

The crystal structure of a new compound NdFeSb3 has been determined by X-ray powder diffraction using the Rietveld method. The compound crystallizes in the orthorhombic, space group Pbcm (No.57) with the CeNiSb3 structure type and lattice parameters a=1.26828(2)nm, b=0.61666(2)nm, c=1.81867(4) nm, z=12 and Dcalc=7.917g/cm3.

Ba4YZr3F23 and Ba4LnZr3F23: a new noncentrosymmetric potential host structure type for optical devices

2019 ◽  
Vol 75 (11) ◽  
pp. 1488-1493
Author(s):  
Jean-Paul Laval ◽  
Abdelkrim Taoudi
Keyword(s):  
Crystal Structure ◽  
Composition Range ◽  
Structure Type ◽  
Optical Devices ◽  
Fluoride Glasses ◽  
Space Group ◽  
Potential Host ◽  
Centrosymmetric Space Group ◽  
Host Structure ◽  
Barium Yttrium

The first ternary BaF2–Ln(Y)F3–ZrF4 phases crystallizing near the composition range of fluoride glasses, namely Ba4YZr3F23 (barium yttrium fluoridozirconate) and isotypic Ba4LnZr3F23 (Ln = Yb, Er and Nd), have been synthesized. The crystal structure of Ba4YZr3F23 cannot be correctly determined in the centrosymmetric space group Pnma (R1 = 0.09); it is preferably described in the noncentrosymmetric space group Pn21 a (R1 = 0.028). All cations are located at y = 0.25–0.29 and 0.75–0.79. This new structure type is formed by infinite {[YZr3F23]8−} n columns associating, along [001], YF9 tricapped trigonal prisms, ZrF8 dodecahedra and ZrF7 polyhedra. These columns are interconnected via BaF10+1 and BaF12 irregular polyhedra.

scholarly journals Olivine-type NaCd(AsO4)

2013 ◽  
Vol 69 (11) ◽  
pp. i75-i75 ◽  
Author(s):  
Matthias Weil
Keyword(s):  
Crystal Structure ◽  
Title Compound ◽  
Structure Type ◽  
Site Symmetry ◽  
Space Group ◽  
Tetrahedral Voids ◽  
Hexagonal Closed Packed

The title compound, sodium cadmium orthoarsenate, adopts the olivine [Mg2(SiO4)] structure type in space groupPnma, with Na (site symmetry -1) and Cd (.m.) replacing the two Mg positions, and the AsO4tetrahedron (.m.) the SiO4tetrahedron. The crystal structure is made up of a nearly hexagonal closed-packed arrangement of O atoms stacked along [001]. The Na and Cd atoms occupy one half of the octahedral voids in alternate layers stacked along [100], and one eighth of the tetrahedral voids are occupied by As atoms.

MYb(BH4)4(M= K, Na) from laboratory X-ray powder data

2013 ◽  
Vol 69 (11) ◽  
pp. 1289-1291 ◽  
Author(s):  
Wojciech Wegner ◽  
Tomasz Jaroń ◽  
Wojciech Grochala
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Structure Type ◽  
Space Group ◽  
X Ray ◽  
Mechanochemical Reactions ◽  
Trigonal Prisms

Two new borohydrides, potassium ytterbium tetraborohydride, KYb(BH4)4, and sodium ytterbium tetraborohydride, NaYb(BH4)4, have been synthesizedviamechanochemical reactions in the solid state. The two compounds are isostructural and both crystallize in theCmcmspace group in the structure reported previously for NaSc(BH4)4and KY(BH4)4. This crystal structure is composed of isolated homoleptic [Yb(BH4)4]−anions surrounded byM+cations (M = Na, K). The packing of theM+cations and [Yb(BH4)4]−anions is a distorted variant of the hexagonal NiAs structure type, withM+forming distorted trigonal prisms,i.e.M6. Each second prism surrounds a [Yb(BH4)4]−anion, while the [Yb(BH4)4]−anions are arranged into deformed octahedra around theM+cations.

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