Crystal Structure Of K2 Research Articles

New Dinuclear Macrocyclic Copper(II) Complexes as Potentially Fluorescent and Magnetic Materials.

Two dinuclear copper(II) complexes with macrocyclic Schiff bases K1 and K2 were prepared by the template reaction of (R)-(+)-1,1'-binaphthalene-2,2'-diamine and 2-hydroxy-5-methyl-1,3-benzenedicarboxaldehyde K1, or 4-tert-butyl-2,6-diformylphenol K2 with copper(II) chloride dihydrate. The compounds were characterized by spectroscopic methods. X-ray crystal structure determination and DFT calculations confirmed their geometry in solution and in the solid phase. Moreover, intermolecular interactions in the crystal structure of K2 were analyzed using 3D Hirshfeld surfaces and the related 2D fingerprint plots. The magnetic study revealed very strong antiferromagnetic CuII-CuII exchange interactions, which were supported by magneto-structural correlation and DFT calculations conducted within a broken symmetry (BS) framework. Complexes K1 and K2 exhibited luminescent properties that may be of great importance in the search for new OLEDs. Both K1 and K2 complexes showed emissions in the range of 392-424 nm in solutions at various polarities. Thin materials of the studied compounds were deposited on Si(111) by the spin-coating method or by thermal vapor deposition and studied by scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), and fluorescence spectroscopy. The thermally deposited K1 and K2 materials showed high fluorescence intensity in the range of 318-531 nm for K1/Si and 326-472 nm for the K2/Si material, indicating that they could be used in optical devices.

Exploring the Role of Crystal Water in Potassium Manganese Hexacyanoferrate as a Cathode Material for Potassium-Ion Batteries

The Prussian Blue analogue K2−δMn[Fe(CN)6]1−ɣ∙nH2O is regarded as a key candidate for potassium-ion battery positive electrode materials due to its high specific capacity and redox potential, easy scalability, and low cost. However, various intrinsic defects, such as water in the crystal lattice, can drastically affect electrochemical performance. In this work, we varied the water content in K2−δMn[Fe(CN)6]1−ɣ∙nH2O by using a vacuum/air drying procedure and investigated its effect on the crystal structure, chemical composition and electrochemical properties. The crystal structure of K2−δMn[Fe(CN)6]1−ɣ∙nH2O was, for the first time, Rietveld-refined, based on neutron powder diffraction data at 10 and 300 K, suggesting a new structural model with the Pc space group in accordance with Mössbauer spectroscopy. The chemical composition was characterized by thermogravimetric analysis combined with mass spectroscopy, scanning transmission electron microscopy microanalysis and infrared spectroscopy. Nanosized cathode materials delivered electrochemical specific capacities of 130–134 mAh g−1 at 30 mA g−1 (C/5) in the 2.5–4.5 V (vs. K+/K) potential range. Diffusion coefficients determined by potentiostatic intermittent titration in a three-electrode cell reached 10−13 cm2 s−1 after full potassium extraction. It was shown that drying triggers no significant changes in crystal structure, iron oxidation state or electrochemical performance, though the water level clearly decreased from the pristine to air- and vacuum-dried samples.

Serendipitous formation and characterization of K2[Pd(NO3)4]·2HNO3

Abstract A potassium tetranitratopalladate(II) with the composition K2[Pd(NO3)4] · 2HNO3 was synthesized by a simple solvothermal process in a glass ampoule. The new compound crystallizes in the monoclinic space group P21 /c (no. 14) with the lattice parameters a = 1017.15(4), b = 892.94(3), c = 880.55(3) Å, and β = 98.13(1)° (Z = 2). The crystal structure of K2[Pd(NO3)4] · 2HNO3 reveals isolated complex [Pd(NO3)4]2− anions, which are surrounded by eight potassium cations and four HNO3 molecules. The complex anions and the cations are associated in layers which are separated by HNO3 molecules. K2[Pd(NO3)4] · 2HNO3 can thus be regarded as a HNO3 intercalation variant of β-K2[Pd(NO3)4]. The characterization is based on single-crystal X-ray and powder X-ray diffraction.

Reaction with SO3 in Ionic Liquids: The Example of K2(S2O7)­(H2SO4)

AbstractThe ionic liquid 1‐butyl‐3‐methylimidazolium hydrogensulfate, [bmim]HSO4, turned out to be resistant even to strong oxidizers like SO3. Thus, it should be a suitable solvent for the preparation of polysulfates at low temperatures. As a proof of principle we here present the synthesis and crystal structure of K2(S2O7)(H2SO4), which has been obtained from the reaction of K2SO4 and SO3 in [bmim]HSO4. In the crystal structure of K2(S2O7)(H2SO4) (orthorhombic, Pbca, Z = 8, a = 810.64(2) pm, b = 1047.90(2) pm, c = 2328.86(6) pm, V = 1978.30(8) Å3) two crystallographically unique potassium cations are coordinated by a different number of monodentate and bidentate‐chelating disulfate anions as well as by sulfuric acid molecules. The crystal structure consists of alternating layers of [K2(S2O7)] slabs and H2SO4 molecules. Hydrogen bonds between hydrogen atoms of sulfuric acid molecules and oxygen atoms of the neighboring disulfate anions are observed.

Crystal Structure of K2[C2O6]—First Proof of Existence and Constitution of a Peroxodicarbonate Ion This work was supported by the Deutsche Forschungsgemeinschaft (DFG) and the Fonds der Chemischen Industrie. Research was carried out in part at the National Synchrotron Light Source at Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Division of Materials Sciences and Division of

Mit hochauflösender Röntgen-Pulverdiffraktometrie konnte die erste Kristallstruktur eines Peroxodicarbonats, hergestellt durch Elektrokristallisation bei −20°C, bestimmt werden. Die Konstitution des Peroxodicarbonat-Anions wurde ermittelt, und sämtliche Strukturdetails, einschließlich der Konformation (siehe Bild), können qualitativ anhand traditioneller Bindungskonzepte erklärt werden.

Crystal Structure of K2[C2O6]—First Proof of Existence and Constitution of a Peroxodicarbonate Ion This work was supported by the Deutsche Forschungsgemeinschaft (DFG) and the Fonds der Chemischen Industrie. Research was carried out in part at the National Synchrotron Light Source at Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Division of Materials Sciences and Division of

By using high-resolution X-ray powder diffraction, we have determined the first crystal structure of a peroxodicarbonate compound, synthesized by electrocrystallization at −20°C. The constitution of the peroxodicarbonate anion was established and all structural details, including its conformation (see picture), can be understood qualitatively in terms of classical concepts of the chemical bond.

Formation of a Dimer with a Double Hydroxo Bridge in Nitric Acid Solutions of the Nitrosotetranitrohydroxo Complex of Ruthenium(II). Crystal Structure of K2[RuNO(NO2)3(μ-OH)

Fine yellowish orange crystals of the binuclear complex K2[RuNO(NO2)3(μ-OH)]2 were obtained by the reaction of K2[RuNO(NO2)4OH] with a stoichiometric amount of 0.8 M nitric acid at room temperature. The compound was investigated by IR spectroscopy, X-ray phase analysis (DRON-3M, CuKα radiation), and X-ray diffraction analysis (Nonius CAD-4, MoKα radiation, graphite monochromator, ω scan mode, 1406 reflections). The crystals are poorly soluble in water and practically insoluble in ethanol and acetone; the compound is stable when stored in air. Crystal data for H2K2N8O16Ru2 are: a = 8.596(2), b = 10.111(1), c = 9.537(1) A, β = 104.42(1)°, V = 802.8(2) A3, space group \(P2_1 {\kern 1pt} /{\kern 1pt} c\), Z = 2, ρcalc = 2.691 g/cm3. The structure is built of [RuNO(NO2)3(μ-\(OH)]_2^{2 - } \) complex anions and K+ cations.

Synthesis and Crystal Structure of K2[Pd0.5Pt0.5(NO2)4

Synthesis and Crystal Structure of K2[Pd0.5Pt0.5(NO2)4

Chelating dihydroxamic acids: study of metal speciation and co-ordination compounds with Ni2+ and Cu2+

Solution (potentiometric, absorption, EPR) as well as solid state studies (X-ray, EPR, magnetic susceptibility) have shown that the binding ability of oxalodihydroxamic acid (H2oxha) with two hydroxamic groups next to each other differs distinctly from that observed for aliphatic dihydroxamic acids, HONHOC(CH2)nCONHOH (n = 3–8). H2oxha was found to be a very powerful ligand for NiII and CuII due to an N,N′-chelating binding mode. The availability of the mixed nitrogen–oxygen donor systems results in formation of polymeric complexes with CuII. The crystal structure of K2[Ni(oxha)2]·2H2O has shown two very characteristic features of the dihydroxamic ligand: (i) two short intramolecular hydrogen bonds stabilising very effectively the complex formed and (ii) very specific binding modes of K+ ions, which play a bridging role between [Ni(oxha)2]2− ions. The latter finding demonstrates a capacity of H2oxha-based anionic complex species to form polynuclear complexes with different bridging modes.

Ein neues Baumuster für ein heteronukleares 11 - Valenzelektronensystem: gefaltete 1 ∞[SnBi]2-Zickzack-Ketten in der Struktur von K2[SnBi] / A Novel Structure Pattern for a Heteronuclear 11 Valence Electron System: Folded 1 ∞[SnBi]2- Zigzag Chains in the Structure of K2[SnBi

The compound K2[SnBi] was prepared by reaction of stoichiometric amounts of the elements in graphitized quartz ampoules. K2[SnBi] crystallizes in the orthorhombic system, space group Pbcm (No 57), Z = 4, with a = 680,4(3), b = 1339,(4) and c = 649,9(3) pm. The crystal structure of K2[SnBi] is characterized by folded infinite 1 ∞[SnBi] zigzag chains of alternating Sn and Bi atoms. The chains are bent at each Bi atom, the Sn atoms are located at the fold of the chain. Apart from the two covalent Sn-Bi bonds, each Sn atom has two additional collinear Sn-Sn contacts in direction of the fold of the chain which in terms of partial bonds can be assigned a bond order of one half. The repeating unit of the chain [Sn2Bi2]4− is strongly related to the isoelectronic butterfly [Si4]6− in Ba3Si4.

Reactions of Nitroplatinum Complexes. 2. Reactions of K2[Pt(NO2)4] and Related Complexes with Aqueous Acids (CH3CO2H, HClO4, CF3SO3H, HNO3, and H2SO4): Pathways to Platinum(III) Complexes with Acetate Bridges. Crystal Structure of K2[{Pt(NO2)2(.mu.-CH3CO2)}2].cntdot.H2O

Full title: Reactions of nitroplatinum complexes. 2. Reactions of K2[Pt(NO2)4] and related complexes with aqueous acids (CH3CO2H, HClO4, CF3SO3H, HNO3, and H2SO4): Pathways to platinum(III) complexes with acetate bridges. Crystal structure of K2[{Pt(NO2)22(μ-CH 3CO2)}2]·H2O. Reaction of K2[Pt(15NO2)4] under argon with 1 M HClO4 or CF3SO3H gave an initial blue solution (λmax = 627 nm), due to nitrosyl complexes of platinum(IV). With heating, the color faded, and 195Pt and 15N NMR peaks were observed from cis-[Pt(15NO2)2(H2O)2], [Pt(15NO2)(H2O)3]+, and fac-[Pt(15NO2)3(H2O) 3]+. In air or oxygen, reaction was faster, giving [Pt(H2O)4]2+ as well as mixed nitrito-N/aqua platinum(II) complexes, and larger proportions of platinum(IV) complexes, including [Pt(OH)6]2- in solution, and solid H2[Pt(OH)6]. With 0.5 M H2SO4, reactions were similar, but a greater variety of platinum(IV) complexes were formed, some probably containing coordinated sulfate. With 1 M HNO3, K2[Pt(NO2)6] formed. Reactions of K2[Pt(NO2]4] with aqueous acetic acid gave mixtures of Pt(II) and Pt(IV) mononuclear complexes and dinuclear Pt(III) complexes containing acetate bridges. The composition of the solution depended on the reaction conditions (heated for various times with argon, air, or oxygen above the solution or bubbled through). Crystals of K2[{PtII(NO2)2(μ-CH 3CO2)}2]·H2O were obtained from a reaction under argon, and the crystal structure was determined by X-ray diffraction: space group P1 (no. 2); a = 7.202(2) A; b = 8.987(2) A; c = 13.592(2) A; α = 94.01(2)°; β = 90.68(2)°; γ = 111.04(2)°; Z = 2; R = 0.0371, for 2875 reflections. The structure showed two acetate ligands bridging between cis-Pt(NO2)2 units, with the Pt-Pt distance 2.986(1) A. Reactions of cis-[Pt(NO2)2(H2O)2] with various oxidants in the presence of acetic acid were studied. [{(CH3CO2)PtIII(NO2) 2(μ-CH3CO2)}2]2- is formed by the oxidation of preformed [{PtII(NO2)2(μ-CH3CO 2)}2]2-. Under anaerobic conditions, the major oxidant is HNO3 formed in the reaction mixture. Oxidation of [{PtII(NO2)2(μ-CH3CO 2)}2]2- with NO2 formed in the reaction mixture in the presence of oxygen provides one route to [(O2N)PtIII(NO2)2(μ-CH 3CO2)2PtIII(NO2) 2(O2CCH3)]2-. Continued heating of solutions containing these Pt(III) complexes eventually gave solutions containing [{(CH3CO2)PtIII(NO2)} 2(μ-CH3CO2)3]-.

Crystal and molecular structure of dipotassium 5-carboxylato-2-thiouracilate sesquihydrate

Abstract The crystal structure of K2[5-CO2-2-TU] · 1.5 H2O, C5H5K2N2O4.5S, has been determined at room temperature. The colorless crystals are monoclinic, space group C2/c with unit cell dimensions a = 14.238(6) Å, b = 6.893(4) Å, c = 20.050(4) Å, β = 102.34(2)°, Z = 8 and D x = 1.903 Mg m−3. The structure was solved by direct methods and refined by a full-matrix least-squares procedure to final R = 0.029 using 1494 reflections. The structure is comprised of K+ cations, 5-carboxylate-2-thiouracilate dianions and water molecules in the ratio 4:2:3. The analysis shows that deprotonation of the thionucleobase occurs at the thioamide N(1) atom and at the carboxyl group. The two cations exist in seven coordinate NO5S geometries, one based on a pentagonal bipyramid and the other based on a capped octahedron.

Reaction of potassium sulfate with trimethylaluminum and the crystal structures of K2[Al4Me12SO4] and K2[Al4Me12SO4].0.5p-xylene

Reaction of potassium sulfate with trimethylaluminum and the crystal structures of K2[Al4Me12SO4] and K2[Al4Me12SO4].0.5p-xylene

Crystal structure, and the infrared and Raman spectra, of potassium, hydroxylamine-N,O-disulphonate, K2[O3SONHSO3]. The infrared and Raman spectra of potassium hydroxylaminetrisulphonate sesquihydrate, K3[O3SON(SO3)2]·1.5H2O

The crystal structure of K2[O3SONHSO3] has been determined using three-dimensional X-ray diffraction data with 1 097 observed reflections. Crystals are monoclinic, space group P21/a, with Z= 4 in a cell of dimensions a= 11.009(3), b= 10.040(2), c= 7.483(3)A, and β= 109.49(2)°. The structure was solved by the heavy-atom method and refined by full-matrix least squares to R 0.033. The N–S bond [1.704(3)A] is markedly longer than found for K2[NH(SO3)2] in which both sulphonate groups are bound directly to nitrogen. The infrared (4 000–50 cm–1) and Raman spectra of K2[O3SONHSO3] and K3[O3SON(SO3)2]·1.5H2O and their 15N and 2H derivatives at 77 K are reported and interpreted. Aqueous spectra have also been recorded. The following frequencies were assigned; ν(N–O), 925; ν(N–S), 808; and ν[S–O(N)], ca. 730 cm–1 for K2[O3SONHSO3]; ν(N–O), 930; νasym(N–S), 820; νsym(N–S), 757; and ν[S–O(N)], 708 cm–1 for K3[O3SON(SO3)2]·1.5H2O.

Crystal structure of K2[ReN(NC)4],H2O

Crystal structure of K2[ReN(NC)4],H2O