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.

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.

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.

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].

The Interplay of Open-Shell Spin-Coupling and Jahn-Teller Distortion in Benzene Radical Cation Probed by X-ray Spectroscopy

2020 ◽  
Author(s):  
Marta L. Vidal ◽  
Michael Epshtein ◽  
Valeriu Scutelnic ◽  
Zheyue Yang ◽  
Tian Xue ◽  
...  
Keyword(s):  
High Harmonic ◽  
Open Shell ◽  
Spin Coupling ◽  
High Symmetry ◽  
Teller Distortion ◽  
Spectral Window ◽  
X Ray ◽  
Jahn Teller ◽  
X Ray Absorption ◽  
Jahn Teller Distortion

We report a theoretical investigation and elucidation of the x-ray absorption spectra of neutral benzene and of the benzene cation. The generation of the cation by multiphoton ultraviolet (UV) ionization as well as the measurement of<br>the carbon K-edge spectra of both species using a table-top high-harmonic generation (HHG) source are described in the companion experimental paper [M. Epshtein et al., J. Phys.<br>Chem. A., submitted. Available on ChemRxiv]. We show that the 1sC -> pi transition serves as a sensitive signature of the transient cation formation, as it occurs outside of the spectral window of the parent neutral species. Moreover, the presence<br>of the unpaired (spectator) electron in the pi-subshell of the cation and the high symmetry of the system result in significant differences relative to neutral benzene in the spectral features associated with the 1sC ->pi* transitions. High-level calculations using equation-of-motion coupled-cluster theory provide the interpretation of the experimental spectra and insight into the electronic structure of benzene and its cation.<br>The prominent split structure of the 1sC -> pi* band of the cation is attributed to the interplay between the coupling of the core -> pi* excitation with the unpaired electron<br>in the pi-subshell and the Jahn-Teller distortion. The calculations attribute most of<br>the splitting (~1-1.2 eV) to the spin coupling, which is visible already at the Franck-Condon structure, and estimate the additional splitting due to structural relaxation to<br>be around ~0.1-0.2 eV. These results suggest that x-ray absorption with increased resolution might be able to disentangle electronic and structural aspects of the Jahn-Teller<br>effect in benzene cation.<br>

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

A New One-Dimensional Bimetallic Complex: Cu(en)2Fe(CN)5(NO). Synthesis, Crystal Structure and Magnetic Behaviour

1998 ◽  
Vol 51 (8) ◽  
pp. 661 ◽  
Author(s):  
Hui-Zhong Kou ◽  
Hong-Mei Wang ◽  
Dai-Zheng Liao ◽  
Peng Cheng ◽  
Zong-Hui Jiang ◽  
...  
Keyword(s):  
Copper Complexes ◽  
Bond Distance ◽  
Chain Structure ◽  
Magnetic Behaviour ◽  
Teller Distortion ◽  
Magnetic Investigation ◽  
Jahn Teller ◽  
Cyanide Ligands ◽  
Jahn Teller Distortion ◽  
Shed Light

The nitrosyl cyanide Cu(en)2Fe(CN)5(NO) was prepared by the reaction of Cu(en)2Cl2 and Na2 [Fe(CN)5(NO)].2H2O in aqueous solution. Single-crystal X-ray structure analysis revealed that the complex assumes a cyanide-bridged chain structure in which iron(II) is coordinated by five cyanide ligands and a nitrosyl group, and copper(II) is coordinated by two ethylenediamine ligands and two bridging cyanide ligands. The copper centres display a typical Jahn–Teller distortion characteristic of octahedral copper complexes with bond distance deviations in lattice symmetry from octahedral ideality: Cu-N(equatorial, mean) 2·010(3) Å and Cu-N(axial, mean) 2·569(3) Å. Infrared and ultraviolet studies shed light on the above molecular structure. A magnetic investigation showed the presence of a weak antiferromagnetic interaction (J = -1·06 cm-1) between the copper atoms within each chain through the diamagnetic Fe(CN)5(NO)2- ions.

Synthese und Kristallstruktur von [Hg2(p-SC6H4NO2)]NO3 / Synthesis and Crystal Structure of [Hg2(p-SC6H4NO2)]NO3

1990 ◽  
Vol 45 (8) ◽  
pp. 1193-1196 ◽  
Author(s):  
Klaus Brodersen ◽  
Axel Knörr
Keyword(s):  
Crystal Structure ◽  
Chain Structure ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
Space Group ◽  
X Ray ◽  
Nitrate Ions ◽  
R Value ◽  
A Chain

[Hg2(p-SC6H4NO2)]NO3 is formed by the reaction of p-nitrothiophenol with dimercury(I)-dinitrate in methanol. It crystallizes in the monoclinic space group P21/n with a = 1175.5(9) pm, b = 1079.8(8) pm, c = 876.2(8) pm, β = 110.74(4)° and Z = 4. The crystal structure has been determined by X-ray diffraction and refined to an R-value of 0.052. The results show that the compound exists as a chain structure of [—®S(C6H4NO2)— Hg— Hg—]n with nitrate ions connecting the chains.

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