Synthesis and crystal structure of the rare earth borogermanate EuGeBO5

2017 ◽  
Vol 72 (2) ◽  
pp. 95-99 ◽  
Author(s):  
Yang Chi ◽  
Yan Zhuang ◽  
Sheng-Ping Guo

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.

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Michael Zoller ◽  
Hubert Huppertz

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.


2013 ◽  
Vol 28 (1) ◽  
pp. 13-17 ◽  
Author(s):  
F. Laufek ◽  
A. Vymazalová ◽  
D.A. Chareev ◽  
A.V. Kristavchuk ◽  
J. Drahokoupil ◽  
...  

The (Ag,Pd)22Se6 phase was synthesized from individual elements by silica glass tube technique and structurally characterized from powder X-ray diffraction data. The (Ag,Pd)22Se6 phase crystallizes in Fm$\overline3$m symmetry, unit-cell parameters: a = 12.3169(2) Å, V = 1862.55(5) Å3, Z = 4, and Dc = 10.01 g/cm3. The crystal structure of the (Ag,Pd)22Se6 phase represents a stuffed 3a.3a.3a superstructure of the Pd structure (fcc), where only 4 from 108 available octahedral holes are occupied. Its crystal structure is related to the Cr23C6 structure type.


Crystals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 424
Author(s):  
Katharina V. Dorn ◽  
Ingo Hartenbach

The gadolinium(III) fluoride oxidotungstate(VI), with the formula Gd5FW3O16, represents the first published fluoride-derivative of a rare-earth metal oxidotungstate. It is synthesized by a mixture of GdF3, Gd2O3, and WO3 at 800 °C and a pressure of 2 GPa with the help of a belt press. The title compound crystallizes in the monoclinic space group P21/c (no. 14) with four formula units per unit cell and the following lattice parameters: a = 539.29 (4), b = 1556.41 (12), c = 1522.66 (11) pm, and β = 93.452 (4). The crystal structure comprises five crystallographically distinguishable Gd3+ cations, which are surrounded by either oxide and fluoride anions (Gd1–3) or by oxide anions only (Gd4, Gd5), with coordination numbers ranging between seven and nine. The fluoride anions are trigonal non-planar coordinated by three Gd3+ cations (Gd1–3). The distorted [WO6]6− octahedra in this structure form isolates edge- and vertex-connected entities of the compositions [W2O10]8− and [W2O11]10−, respectively. According to the presented units, a structured formula can be written as Gd4[FGd3]2[W2O10][W2O11]2. The single-crystal Raman spectrum reveals the typical symmetric stretching vibration mode of octahedral oxidotungstate(VI) units at about 871 cm−1.


2017 ◽  
Vol 70 (12) ◽  
pp. 1269
Author(s):  
Steven Gareth Williams ◽  
Mohan Bhadbhade ◽  
Roger Bishop ◽  
Alison Thavary Ung

The reaction of (–)-β-pinene with KCN under a mild bridged Ritter reaction gave (1S,5R,6S)-2,2,6-trimethyl-3-aza-bicyclo[3.3.1]non-3-en-6-yl acetate that subsequently reacted to provide an unexpected (1S,4R,5R,6S)-4-cyano-2,2,6-trimethyl-3-azabicyclo[3.3.1]nonane-6-yl acetate. The structure of the compound was determined by high-resolution mass spectrometry, and IR and NMR spectroscopy and confirmed by single crystal X-ray crystallography. The compound crystallises in the monoclinic P21 space group, with unit cell parameters a 8.6120 (17), b 7.4570 (15), c 11.189 (2) Å, and β 110.16 (3)°.


2000 ◽  
Vol 55 (3-4) ◽  
pp. 238-242 ◽  
Author(s):  
A. B. M. Shamsur Rahman ◽  
H. Boiler ◽  
K. O. Klepp

Abstract Red-brown crystals of a new bis(thiomolybdate) complex [Me4N]3[(MoOS3)2Ag] were formed at room temperature through the reaction of a solution of [Me4N]2[MoOS3] in MeCN with solid AgCN. They are monoclinic, space group P21/c with unit cell parameters a = 16.662(9), b = 9.464(3), c = 17.890(8) A, /3 = 101.87(2)°, Z = 4. The crystal structure was determined from single crystal diffractometer data (MoKα-radiation) and refined to R = 0.044 (3614 reflections, 236 variable parameters). The structure is characterized by trinuclear complex anions, [(MoOS3)2Ag]3-. According to Weissenberg investigations the homologous tungsten compound is isostructural. The infrared spectrum of the molybdenum complex (KBr powder) shows absorption bands at 884 (vs) and 871 (w) cm-1 (terminal v(Mo-0)), 483 (vs) cm-1 (terminal v(Mo-S)), 451 (vs), and 435 (w) cm-1 (bridging v(Mo-S)). The tungsten complex showed bands at 901 (vs) cm-1 (terminal v(W-O)), 478 (vs) cm-1 (terminal v(W-S)), and 435 (vs) cm-1 (bridging v(W-S)). The anionic mass spectra shows molecular ion peaks at m/z 524 and 700 for [(MoOS3)2Ag]- and [(WOS3)2Ag]-, respectively, as well as peaks for other fragments.


2008 ◽  
Vol 23 (3) ◽  
pp. 232-240
Author(s):  
Abderrahim Aatiq ◽  
Rachid Bakri ◽  
Aaron Richard Sakulich

Synthesis and structure of two phosphates belonging to the ternary Sb2O5–In2O3–P2O5 system are realized. Structures of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7 phases, obtained by solid state reaction in air at 950 °C, were determined at room temperature from X-ray powder diffraction using the Rietveld method. SbV1.50InIII0.50(PO4)3 have a monoclinic (space group P21/n) distortion of the Sc2(W O4)3-type framework. Its structure is constituted by corner-shared SbO6 or InO6 octahedra and PO4 tetrahedra. Monoclinic unit cell parameters are a=11.801(2) Å, b=8.623(1) Å, c=8.372(1) Å, and β=90.93(1)°. (Sb0.50In0.50)P2O7 is isotypic with (Sb0.50Fe0.50)P2O7 and crystallizes in orthorhombic system (space group Pna21) with a=7.9389(1) Å, b=16.0664(2) Å, and c=7.9777(1) Å. Its structure is built up from corner-shared SbO6 or InO6 octahedra and P2O7 groups (two group-types). Each P2O7 group shares its six vertices with three SbO6 and three InO6 octahedra, and each octahedron is connected to six P2O7 groups.


2019 ◽  
Vol 65 (4 Jul-Aug) ◽  
pp. 355 ◽  
Author(s):  
G. E. Delgado ◽  
And V. Sagredo

The crystal structure of the quaternary compound Cu2NiGeS4, belonging to the system I2-II-IV-VI4, was characterized by Rietveld refinement using X-ray powder diffraction data. This material crystallize with a stannite structure in the tetragonal space group I2m (Nº 121), Z = 2, unit cell parameters a = 5.3384(1) Å, c = 10.5732(3) Å, V = 301.32(3) Å3, acknowledged as a normal valence adamantane-structure.


Author(s):  
Analio Dugarte-Dugarte ◽  
Nahum Ramírez Pineda ◽  
Luis Nieves ◽  
José Antonio Henao ◽  
Graciela Díaz de Delgado ◽  
...  

Almost 50 years after the initial report, the crystal structure of Cu2GeSe3, a I2-IV-VI3 semiconductor, has been revised using modern single-crystal X-ray diffraction data. The structure of this material can be properly described in the monoclinic space group Cc (No. 9) with unit-cell parameters a = 6.7703 (4) Å, b = 11.8624 (5) Å, c = 6.7705 (4) Å, β = 108.512 (6)°, V = 515.62 (5) Å3, Z = 4, rather than in the orthorhombic space group Imm2 (No. 44) with unit-cell parameters a = 11.860 (3), b = 3.960 (1), c = 5.485 (2) Å, V = 257.61 Å3, Z = 2, as originally proposed [Parthé & Garín (1971). Monatsh. Chem. 102, 1197–1208]. Contrary to what was observed in the orthorhombic structure, the distortions of the tetrahedra in the monoclinic structure are consistent with the distortions expected from considerations derived from the bond valence model. A brief revision of the structures reported for the I2-IV-VI3 family of semiconducting compounds (I: Cu, Ag; IV: Si, Ge, Sn; and VI: S, Se, Te) is also presented.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Akhmatkhodja N. Yunuskhodjayev ◽  
Shokhista F. Iskandarova ◽  
Vahobjon Kh. Sabirov

Abstract The crystal structure of a copper(II) complex of protonated sildenafil, CuCl3C22H31N6O4S⋅2H2O was studied by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 15.4292(2), b = 9.06735(12), c = 21.1752(2) Å, V = 2945.48(7) Å3, Z = 4. The Cu atom is coordinated by the sildenafil ligand via the N2 atom of the pyrazolopyrimidine ring and by three chloride anions. Sildenafil is protonated at the methylated N6 atom of the piperazine ring and it is cation ligand with a 1+ charge.


Sign in / Sign up

Export Citation Format

Share Document