Dimerization of a mixed-carbene PdII dibromide complex by elemental iodine

2017 ◽  
Vol 73 (12) ◽  
pp. 1131-1136 ◽  
Author(s):  
Christian Jandl ◽  
Alexander Pöthig
Keyword(s):  
Single Crystal ◽  
Bulk Material ◽  
Dimeric Complex ◽  
Carbene Complex ◽  
Counter Ions ◽  
Square Planar ◽  
Complex Features ◽  
Elemental Iodine

A monomeric PdII complex bearing a mixed carbocyclic/N-heterocyclic carbene ligand and two bromides was reacted with an excess of elemental iodine, which resulted in the surprising removal of one bromide ligand and dimerization of the mixed-carbene complex to form di-μ-bromido-bis{[1-(cyclohepta-2,4,6-trien-2-yl-1-ylidene-κC 1)-3-(2,6-diisopropylphenyl)imidazol-2-ylidene]palladium(II)} bis(pentaiodide) dichloromethane monosolvate, [Pd2Br2(C22H24N2)2](I5)2·CH2Cl2. The dimeric complex features a slightly distorted square-planar core of two PdII centres bridged by two bromide ligands, which lie in the same plane as the seven- and five-membered rings of the bidentate carbene ligand. The counter-ions in the single crystal were found to be pentaiodide monoanions featuring their typical V-shape, whereas for the bulk material, a mixture of Br/I interhalides is proposed.

The Ternary Rare Earth Chromium Nitrides Ce2CrN3 and Ln3Cr10−xN11 with Ln = La, Ce, Pr

1995 ◽  
Vol 50 (6) ◽  
pp. 905-912 ◽  
Author(s):  
Sascha Broil ◽  
Wolfgang Jeitschko
Keyword(s):  
Rare Earth ◽  
Single Crystal ◽  
Chromium Nitrides ◽  
First Approximation ◽  
Structure Factors ◽  
Square Planar ◽  
Pauli Paramagnetism ◽  
Cubic Structure ◽  
Cold Pressed ◽  
N Flux

The title compounds have been prepared by annealing cold-pressed pellets of the binary nitrides LnN and CrN. Well developed crystals were obtained by recrystallization of the binary or prereacted ternary nitrides in a Li3N flux. Their structures were determined from single-crystal diffractometer data. C e2CrN3 has a U2CrN3 type structure: Immm , a = 379.0(1), b = 340.4(1), c = 1251.7(2) pm, Z = 2, R = 0.012 for 383 structure factors and 16 variables. The atomic positions of this structure are similar to those of U2IrC2 and K2NiF4. The structure may be rationalized to a first approximation with the formula (Ce+4)2[CrN3]8−. The chromium atoms are in a distorted square-planar nitrogen coordination. The CrN4-squares are linked via corner-sharing nitrogen atoms, thus forming infinite, straight - N - CrN2- N - CrN2- chains. The cubic structure of La3Cr10−xN11 (a = 1298.2(1) pm ), Ce3Cr10−xN11 (with a small homogenity range; a = 1284.3(1)-1286.1(3) pm ), and Pr3Cr10−xN11 (a = 1289.1(2) pm ) was determined for the lanthanum compound: Fm 3̄ m , Z = 8, R = 0.027 for 189 F values and 18 variables. One chromium site was found to have an occupancy of only 80.9(5)% resulting in the composition La3Cr9.24(1)N11. The nitrogen atoms occupy four atomic sites. Three of these have octahedral environments (6 La, 3 La + 3 Cr, 2 La + 4 Cr), the fourth one is surrounded by eight chromium atoms forming a cube. The chromium atoms are tetrahedrally coordinated by nitrogen atoms, and these CrN4-tetrahedra are linked via common corners and edges to form a three-dimensionally infinite polyanionic network. In addition the chromium atoms with oxidation numbers of about 2 to 3 form numerous Cr - Cr bonds, which allow to rationalize the Pauli paramagnetism of the compound.

scholarly journals Syntheses, Characterization, Crystal Structures and Antimicrobial Activity of Schiff Base Copper(II) Complexes Derived from 2-Bromo-6-((2-(isopropylamino) ethylimino)methyl)phenol

2021 ◽  
Vol 68 (4) ◽  
pp. 1008-1015
Author(s):  
Yong Yuan ◽  
Xi-Kun Lu ◽  
Gao-Qi Zhou ◽  
Xiao-Yang Qiu
Keyword(s):  
Antimicrobial Activity ◽  
Schiff Base ◽  
Single Crystal ◽  
Elemental Analysis ◽  
Structure Determination ◽  
Antimicrobial Activities ◽  
X Ray ◽  
Zwitterionic Form ◽  
Square Planar ◽  
Vis Spectroscopy

Three new copper(II) complexes, [Cu(LH)2]Br2 (1), [Cu(LH)2]NCS2 (2), and [Cu(LH)2](NO3)2 (3), where LH is the zwitterionic form of 2-bromo-6-((2-(isopropylamino)ethylimino)methyl)phenol (HL), were synthesized and characterized by elemental analysis, IR and UV-vis spectroscopy. The structures of the complexes were further confirmed by single crystal X-ray structure determination. All compounds are mononuclear copper(II) complexes. The Cu atoms in the complexes are coordinated by two imino N and two phenolate O atoms from two LH ligands, forming square planar coordination. The compounds were assayed for their antimicrobial activities.

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

IUCrData ◽  
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].

scholarly journals Synthesis of a Square-Planar Rhodium Alkylidene N-Heterocyclic Carbene Complex and Its Reactivity Toward Alkenes

2011 ◽  
Vol 30 (19) ◽  
pp. 5208-5213 ◽  
Author(s):  
Laura Palacios ◽  
Xiaowei Miao ◽  
Andrea Di Giuseppe ◽  
Simon Pascal ◽  
Carmen Cunchillos ◽  
...  
Keyword(s):  
Carbene Complex ◽  
Square Planar

scholarly journals Giant anisotropic thermal expansion actuated by thermodynamically assisted reorientation of imidazoliums in a single crystal

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Zi-Shuo Yao ◽  
Hanxi Guan ◽  
Yoshihito Shiota ◽  
Chun-Ting He ◽  
Xiao-Lei Wang ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Single Crystal ◽  
Molecular Motion ◽  
Bulk Material ◽  
Shape Change ◽  
Variable Temperature ◽  
Negative Thermal Expansion ◽  
Formidable Challenge ◽  
Potential Applications ◽  
Molecular Cations

Abstract Materials demonstrating unusual large positive and negative thermal expansion are fascinating for their potential applications as high-precision microscale actuators and thermal expansion compensators for normal solids. However, manipulating molecular motion to execute huge thermal expansion of materials remains a formidable challenge. Here, we report a single-crystal Cu(II) complex exhibiting giant thermal expansion actuated by collective reorientation of imidazoliums. The circular molecular cations, which are rotationally disordered at a high temperature and statically ordered at a low temperature, demonstrate significant reorientation in the molecular planes. Such atypical molecular motion, revealed by variable-temperature single crystal X-ray diffraction and solid-state NMR analyses, drives an exceptionally large positive thermal expansion and a negative thermal expansion in a perpendicular direction of the crystal. The consequent large shape change (~10%) of bulk material, with remarkable durability, suggests that this complex is a strong candidate as a microscale thermal actuating material.

Tetrahalogenotellurate(II): Synthese und Kristallstrukturen von Verbindungen mit den Ionen TeX42- (X = Cl, Br, I)/Tetrahalotellurates(II): Syntheses and Crystal Structures of Compounds with TeX42- Ions (X = Cl, Br, I)

1985 ◽  
Vol 40 (2) ◽  
pp. 251-257 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Bernt Krebs
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Acetonitrile Solution ◽  
Monoclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
Square Planar

Abstract The compounds [(C6H5)4As]2 TeCl4 (1), [(C2H5)4 N]2 TeBr4 · CH3CN (2), and [(C2H5)4N]2TeI4 (3) were prepared by the reaction of Te, X2 , and excess (C2H5)4NX (X = Br, I) in acetonitrile solution or by heating of [(C6H5)4 As]2TeCl6 , Te, and (C6H5)4 ASCl for several hours in the same solvent.The structures of 1-3 were determined from single crystal X-ray data.1 crystallizes in the monoclinic space group P21/n with a = 1061.8(2), b = 1614.2(3), c = 1341.7(3) pm, β = 94.21° and Z = 2; 2: tetragonal, P4/mmm, a = 1039.7(2), c = 690.5(1), Z = 1; 3: tetragonal, I4/mmm, a = 1061.7(2), c = 1342.8(4), Z = 2. In 1-3 Te(II) exhibits a square planar coordination. The Te -CI, Te -Br, and Te-I bond lengths were found to be 260.7 (mean), 275.3, and 298.5 pm, respectively.

Synthesis and structure of 4-methylpyridine complexes of cobalt(II) and nickel(II) hexafluorophosphate and hexafluoroarsenate

1978 ◽  
Vol 56 (7) ◽  
pp. 985-991 ◽  
Author(s):  
Raymond M. Morrison ◽  
Robert C. Thompson
Keyword(s):  
Magnetic Properties ◽  
Field Strength ◽  
Single Crystal ◽  
Infrared Spectra ◽  
Electronic Spectra ◽  
Preliminary Report ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
X Ray ◽  
Square Planar

The complexes M(4mepy)4A2 and M(H2O)2(4mepy)8A2 (where M is Ni or Co and A is PF6 or AsF6) have been prepared and their electronic spectra and magnetic properties studied. A preliminary report is made of single crystal X-ray diffraction studies on Ni(H2O)2(4mepy)8(PF6)2, Co(H2O)2(4mepy)8(PF6)2, and Co(4mepy)4(PF6)2. All of the complexes have structures involving complex cations and non-coordinated anions, consistent with extremely weak ligating abilities for both PF6− and AsF6−. Cations identified and characterized are the squashed tetrahedral [Co(4mepy)4]2+ ion, the square planar [Ni(4mepy)4]2+ ion, and the tetragonal [Co(4mepy)4((4mepy)2H2O)2]2+and [Ni(4mepy)4((4mepy)2H2O)2]2+ ions. The ligand field strength of 4-methylpyridine is found to be indistinguishable from that of pyridine in these complexes. Infrared spectra are reported and infrared criteria for establishing the presence of non-coordinated anions in PF6− and AsF6− complexes are suggested.

SU-79: a novel germanate with 3D 10- and 11-ring channels templated by a square-planar nickel complex

2014 ◽  
Vol 1 (3) ◽  
pp. 278-283 ◽  
Author(s):  
Shiliang Huang ◽  
Jie Su ◽  
Kirsten Christensen ◽  
A. Ken Inge ◽  
Jie Liang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electron Diffraction ◽  
Single Crystal ◽  
Nickel Complex ◽  
X Ray Diffraction ◽  
X Ray ◽  
Open Framework ◽  
Square Planar

An open-framework germanate SU-79 was synthesized using nickel complex and amine as the templates. The crystal structure was solved by the combination of rotation electron diffraction (RED) and synchrotron single crystal X-ray diffraction.

Vibrations moléculaires du nitrate de di-μ-hydroxo-bis(diammine) platine (II) [(NH3)2Pt(OH)2Pt(NH3)2](NO3)2. Partie 2: analyse en coordonnées normales

1982 ◽  
Vol 60 (17) ◽  
pp. 2222-2228 ◽  
Author(s):  
Alain J. P. Alix ◽  
Michel Manfait ◽  
Odile Krug ◽  
Théophile Theophanides
Keyword(s):  
Vibrational Energy ◽  
Normal Modes ◽  
Dimeric Complex ◽  
Normal Coordinate ◽  
Model Approximation ◽  
Mass Model ◽  
Deuterated Analog ◽  
Square Planar ◽  
Modes Of Vibration ◽  
Related Compounds

A full normal coordinate analysis of the skeleton [N2′ Pt O2′ Pt N2′] of the di-μ-hydroxo-bis(diammine) platinum(II) nitrate has been performed according to the Point Mass Model approximation and assuming a D2h molecular symmetry.The method of construction of a set of 18 independent symmetry valence coordinates was based on the theory of molecular vibrations in dependent rectilinear coordinates. A refined general valence force field which reproduces satisfactorily the frequencies of the molecule and its deuterated analog has been obtained. Calculations of all distributions of vibrational energy allow us to descry ibe all normal modes of vibration and especially the ones related to the square planar ring modes (Pt2O2) showing evidence of strong couplings.In addition we have calculated independently some fragments of the whole dimeric complex, which may be used for comparison with related compounds.

scholarly journals Redetermination of the crystal structure of caesium tetrafluoridobromate(III) from single-crystal X-ray diffraction data

IUCrData ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Artem V. Malin ◽  
Sergei I. Ivlev ◽  
Roman V. Ostvald ◽  
Florian Kraus
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Diffraction Data ◽  
Point Group ◽  
Group Symmetry ◽  
Site Symmetry ◽  
X Ray Diffraction ◽  
Cation Site ◽  
X Ray ◽  
Square Planar

Caesium tetrafluoridobromate(III), CsBrF4, was crystallized in form of small blocks by melting and recrystallization. The crystal structure of CsBrF4 was redetermined from single-crystal X-ray diffraction data. In comparison with a previous study based on powder X-ray diffraction data [Ivlev et al. (2013). Z. Anorg. Allg. Chem. 639, 2846–2850], bond lengths and angles were determined with higher precision, and all atoms were refined with anisotropic displacement parameters. It was confirmed that the structure of CsBrF4 contains two square-planar [BrF4]− anions each with point group symmetry mmm, and a caesium cation (site symmetry mm2) that is coordinated by twelve fluorine atoms, forming an anticuboctahedron. CsBrF4 is isotypic with CsAuF4.

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