Die Kristallstrukturen von Na2CoFeF7 und einer zweiten Modifikation von Na2CuFeF7: Eine weitere Weberit-Variante / The Crystal Structures of Na2CoFeF7 and a Second Modification of Na2CuFeF7: Another Weberite Variant

1992 ◽  
Vol 47 (5) ◽  
pp. 685-692 ◽  
Author(s):  
Matthias Welsch ◽  
Dietrich Babel
Keyword(s):  
Crystal Structures ◽  
The Other ◽  
Intermediate Type ◽  
Teller Distortion ◽  
Space Group ◽  
Jahn Teller ◽  
Structural Relations ◽  
Jahn Teller Distortion

The monoclinic weberites Na2CoFeF7 (a = 1262.2(10), b = 736.0(4), c = 2451.6(20) pm, β = 99.71(5)°) and a second modification of Na2CuFeF7 (a = 1244.4(2), b = 734.3(1), c = 2467.2(5) pm, β = 99.27(3)°), crystallize isotypically in space group C 2/c, Ζ = 16. The structure is an intermediate type between orthorhombic and trigonal weberites, characterized by pairs ofparallel chains of octahedra [MF4F2/2]3- (M = Co, Cu) which run in turn along [110] and [110]. The average distances are Fe-F = 192 pm in the [FeF63- octahedra of both compounds. Considerable splitting of distances occurs in the [CoF6- octahedra (av. Co-F = 201 pm), and by Jahn-Teller distortion even more in those of [CuFJ4- (av. Cu-F = 199 pm). One of the copper surroundings is (pseudo)tetragonally elongated (av. 209/194 pm), the other exhibits an unusual splitting into three long and three short bonds (av. 204/193 pm) in meridional positions. Some structural relations are discussed.

scholarly journals Die Jahn-Teller-Verzerrung in den Kristallstrukturen der Dinatrium-Tetrafluorometallate Na2CuF4 und Na2CrF4 / The Jahn-Teller Distortion in the Crystal Structures of the Disodium-Tetrafluorometallates Na2CuF4 and Na2CrF4

1989 ◽  
Vol 44 (7) ◽  
pp. 715-720 ◽  
Author(s):  
Dietrich Babel ◽  
Michael Otto
Keyword(s):  
Crystal Structures ◽  
Chain Structure ◽  
Teller Distortion ◽  
Space Group ◽  
X Ray ◽  
Edge Sharing Octahedra ◽  
Jahn Teller ◽  
A Chain ◽  
Jahn Teller Distortion ◽  
Ray Methods

The crystal structures of the isotypic monoclinic fluorides Na2CuF4 (a = 326.7(1), b = 937.0(2), c = 561.2(1) pm, β = 92.49(1)°; V = 171.63 x10-30 m3) and Na2CrF4 (a = 334.8(1), b = 954.9(2), c = 566.5(3) pm, β = 92.85(3)°; V = 180.89 × 10-30 m3) have been redetermined by single crystal X-ray methods. The compounds are Jahn-Teller distorted variants of the orthorhombic Sr2PbO4type (space group Pbam) and crystallize with Z = 2 in space group P21/c, a subgroup of Pbam. They form a chain structure of edge-sharing octahedra which are strongly elongated. The following distances were obtained: Cu-F = 190.4/193.8/235,7(2) pm and Cr-F = 199.1/199.7/241.7(4) pm. The geometry is compared to that of the corresponding distorted rutile type difluorides; relations to further compounds are discussed.

Zur Struktur der Kupfer-Weberite Na2CuCrF7 und Na2CuFeF7 / Concerning the Structures of the Copper Weberites Na2CuCrF7 and Na2CuFeF7

1988 ◽  
Vol 43 (6) ◽  
pp. 694-701 ◽  
Author(s):  
S. Kummer ◽  
W. Massa ◽  
D. Babel
Keyword(s):  
Crystal Structure ◽  
The Body ◽  
Intermediate Type ◽  
Teller Distortion ◽  
Mean Values ◽  
Space Group ◽  
Preliminary Results ◽  
Jahn Teller ◽  
Jahn Teller Distortion

AbstractThe crystal structure of the compound Na-CuCrF7 (orthorhombic, a = 710.0, b = 1033.8, c = 751.8 pm, Z = 4) was refined in space group Pmnb to Rg= 0.028 (1545 independent reflections). The Jahn-Teller distortion of the CuF6 -octahedra (Cu-F = 191.1/193.8/212.4 pm. mean 199.1 pm) reduces the symmetry compared to the body-centered orthorhombic weberite type, to which it is otherwise closely related. The CrF6 -octahedra. interconnecting parallel chains of CuF6 -octahedra, are nearly undistorted (mean Cr-F = 190.6 pm). Na2CuFeF7 exhibits a supercell with a different structure (monoclinic, a = 2468.7, b = 734.7, c = 1245.2 pm, β = 99.29°, Z = 16). It may be interpreted as a new intermediate type between orthorhombic and trigonal weberites. Preliminary results obtained from refinement in space group A2/n (Rg = 0.076) are given and discussed (mean values Cu-F = 199 pm, Fe - F = 192 pm).

The crystal structures of the Hexakis(pyridine 1-oxide) complexes of copper(II), cobalt(II) and iron(II) perchlorates

1978 ◽  
Vol 31 (4) ◽  
pp. 713 ◽  
Author(s):  
D Taylor
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Teller Distortion ◽  
Space Group ◽  
X Ray ◽  
Perchlorate Ion ◽  
Fourier Techniques ◽  
Jahn Teller ◽  
Jahn Teller Distortion ◽  
Block Diagonal

The crystal structures of the isomorphous complexes [M(pyridine 1-oxide)6] (ClO4)2 M = Cu (1), Co (2) and Fe (3), have been determined from X-ray diffractometer data collected at 293 K. The complexes crystallize in the rhombohedral space group R3 with Z = 1; cell constants for (1): a 9.605(1)Ǻ, α 81.10(1)°; for (2): a 9.619(1)Ǻ, α 81.19(1)°; for (3): a 9.640(1)Ǻ, α 81.06(1)°. The structures were solved by Fourier techniques and refined by block-diagonal least squares to convergence at R, R': (1) 0.037, 0.039 for 1009 reflections; (2) 0.030, 0.038 for 812 reflections; (3) 0.032, 0.041 for 780 reflections with I ≥ 3σ(I). The cations have exact S6 symmetry with the MO6 moiety having almost exact Oh symmetry, which implies for (1) a lack of a static Jahn-Teller distortion. The M-O distances increase (1) 2.076(2), (2) 2.090(1), (3) 2.112(2)Ǻ in the order expected. The geometries of the pyridine 1-oxide ligand and the perchlorate ion are consistent over the three determinations and are normal.

Crystal structures and phase transition in (Sr0.8Ce0.2)(Mn1−yCoy)O3(y= 0 and 0.2): the influence of Jahn–Teller distortion

2009 ◽  
Vol 21 (12) ◽  
pp. 124218 ◽  
Author(s):  
Zhaoming Zhang ◽  
Christopher J Howard ◽  
Brendan J Kennedy ◽  
Motohide Matsuda ◽  
Michihiro Miyake
Keyword(s):  
Phase Transition ◽  
Crystal Structures ◽  
Teller Distortion ◽  
Jahn Teller ◽  
Jahn Teller Distortion

The crystal chemistry of duftite, PbCuAsO4(OH) and the β-duftite problem

1998 ◽  
Vol 62 (1) ◽  
pp. 121-130 ◽  
Author(s):  
Kharisun ◽  
Max R. Taylor ◽  
D. J. M Bevan ◽  
Allan Pring
Keyword(s):  
Hydrogen Bonding ◽  
Crystal Chemistry ◽  
Three Dimensional ◽  
The Other ◽  
Orthorhombic Space Group ◽  
Teller Distortion ◽  
Modulated Structure ◽  
Dimensional Network ◽  
Jahn Teller ◽  
Jahn Teller Distortion

AbstractDuftite, PbCu(AsO4)(OH) is orthorhombic, space group P212121 with a = 7.768(1), b = 9. 211(1), c = 5.999(1) Å, Z = 4; the structure has been refined to R = 4.6% and Rw = 6.5% using 640 observed reflections [F> 2σ(F)]. The structure consists of chains of edge-sharing CuO6 ‘octahedra’, parallel to c; which are linked via AsO4 tetrahedra and Pb atoms in distorted square antiprismatic co-ordination to form a three dimensional network. The CuO6 ‘octahedra’ show Jahn-Teller distortion with the elongation running approximately along <627>. The hydrogen bonding network in the structure was characterized using bond valence calculations. ‘β-duftite’ is an intermediate in the duftite-conichalcite series, which has a modulated structure based on the intergrowth of the two structures in domains of approximately 50 Å. The origin of the modulation is thought to be associated with displacements in the oxygen lattice and is related to the orientation of the Jahn-Teller distortion of CuO6 ‘octahedra’. Approximately half of the strips show an elongation parallel to <627> while the other strips are elongated parallel to [010]. This ordering results in an increase in the b cell repeat compared to duftite and conichalcite.

The Preparation and Crystal Structure of Ammonium Bis[citrato(3-)]cuprate(II)

1991 ◽  
Vol 44 (10) ◽  
pp. 1495 ◽  
Author(s):  
RC Bott ◽  
DS Sagatys ◽  
DE Lynch ◽  
G Smith ◽  
CHL Kennard ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Citric Acid ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Teller Distortion ◽  
Space Group ◽  
X Ray ◽  
Jahn Teller ◽  
A Cell ◽  
Jahn Teller Distortion

The copper(II) complex with citric acid (NH4)4 [Cu(C6H5O7)2] has been prepared, and its structure determined by X-ray diffraction, giving a residual R 0.035 for 1208 observed reflections. Crystals are monoclinic, space group P21/c with Z 2 in a cell of dimensions a 8.755(3), b 13.185(4), c 9.364(2)Ǻ, β 113.73(2)°. The complex is a centrosymmetric six-coordinate monomer which is isomorphous with ammonium zinc(II) citrate. However, the Cu-O(hydroxyl) bonds [2.341(3)Ǻ] show Jahn-Teller distortion relative to the Cu-O(carboxyl) bonds [1.969(3) and 1.977(3)Ǻ].

scholarly journals Anisotropic strain and Jahn-Teller effect of chiral complexes and metal oxides

2014 ◽  
Vol 70 (a1) ◽  
pp. C179-C179
Author(s):  
Yuta Orii ◽  
Masaki Kobayashi ◽  
Yuki Nagai ◽  
Kohei Atsumi ◽  
Daichi Tazaki ◽  
...  
Keyword(s):  
Composite Materials ◽  
Crystal Structures ◽  
Lattice Strain ◽  
Variable Temperature ◽  
Teller Distortion ◽  
Coordination Environment ◽  
Jahn Teller ◽  
Anisotropic Lattice ◽  
Jahn Teller Effect ◽  
Jahn Teller Distortion

For about a decade, we have systematically investigated thermally-accessible lattice strain and local pseudo Jahn-Teller distortion of [CuL2]3[M(CN)6]2·4H2O (L = (1R, 2R)-cyclohexanediamine; M = Cr, Co, and Fe). In mononuclear Cu(II) complexes, (pseudo) Jahn-Teller effect plays an important role in flexible distortion of crystal structures especially Cu(II) coordination environment. Beside Jahn-Teller distortion, we have dealt with some factors for example, metal substitution as bimetallic assemblies, chirality of ligands, and H/D isotope effect to vary intermolecular interaction and crystal packing. According to the course work using variable temperature PXRD, we have found that anisotropy of crystal strain distortion did not corporate with Jahn-Teller distortion around local coordination environment because of the discrepancy of the crystallographic axes and molecular alignment. In order to elucidate the anisotropic control of lattice strain and Jahn-Teller distortion closely, we have employed transition metal oxide with orthogonal or layered structures to prepare composite materials with the chiral metal complexes for discussion of thermally-accessible PXRD changes and IR shift due to adsorption. At first, we have employed chiral one-dimensional zig-zag Cu-Cr bimetallic assemblies and their oxides prepared by burining. Based on variable temperature XRD patterns, a linear correlation (lnK = a/T + b) of K (=d(T)-d(0)/d(T)) values, where d(T) and d(0) are spacing of lattice plane (d = nλ/(2sinθ)) at T K and 0 K (extrapolated), respectively, and its deviation from ideal correlation indicates degree of anisotropic lattice distortion of the composite materials. For example, we could observe LiMnO2, typical material of lithium ion battery, was enhanced anisotropic lattice strain along the b axis or the (011) plane added by [CuL2(H2O)2](NO3)2 complexes. Which may prevent from breaking down regular crystal structures during charge-discharge of secondary battery.

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