13400-13-0Relevant articles and documents
PREPARATION OF Rb2NaYF6:Ce3 + AND Cs2NaYF6:Ce3 + - A PROSPECT FOR TUNABLE LASERS IN THE BLUE-GREEN WAVELENGTH.
Mroczkowski,Dorain
, p. 259 - 265 (1985)
A systematic study of the systems RbF-NaF-YF//3 and NaF-CsF-YF//3 has been made in order to synthesize Ce**3** plus -doped Rb//2NaYF//6 and Cs//2NaYF//6. Based on preliminary results of the absorption fluorescence efficiency, lifetime, and excited-state absorption, we conclude that a series of compounds (in the form of single crystals) of the general form A//2BYF//6:Ce**3** plus is a worthy prospect for a broad-band, wavelength tunable laser from 400 to 480 mu m which makes it attractive for optical communication.
Complexes of xenon oxide tetrafluoride
Selig, Henry
, p. 183 - 186 (1966)
Xenon oxide tetrafluoride bears a strong resemblance to the halogen fluorides both in physical properties and chemical behavior. A number of physical properties of XeOF4 have been measured. Xenon oxide tetrafluoride is a clear, colorless liquid freezing at -46.2°. Its electrical conductivity at 24° is 1.03 × 10-5 ohm-1 cm.-1 and its dielectric constant is 24.6 at 24°. It is miscible with anhydrous HF, but its conductivity is not enhanced in such a solution. The addition of CsF or RbF to XeOF4 increases its conductivity markedly. Xenon oxide tetrafluoride forms a series of addition compounds with the heavier alkali fluorides. The following complexes have been isolated: CsF·XeOF4, 3RbF-2XeOF4 and 3KF·-XeOF4. No reaction occurs with NaF. Thermogravimetric studies show that a number of intermediates are formed before final decomposition to the alkali fluorides. Xenon oxide tetrafluoride reacts with SbF5 to form a complex of composition XeOF4· 2SbF5. A reaction also occurs with AsF5 at -78°, but the complex is unstable at room temperature.
Soluble diamagnetic model for malaria pigment: Coordination chemistry of gallium(III)protoporphyrin-IX
Bohle, D. Scott,Dodd, Erin L.,Pinter, Tyler B. J.,Stillman, Martin J.
, p. 10747 - 10761 (2012)
The facile axial ligand exchange properties of gallium(III) protoporphyrin IX in methanol solution were utilized to explore self-association interactions by NMR techniques. Structural changes were observed, as well as competitive behavior with the ligands acetate and fluoride, which differed from that seen with the synthetic analogue gallium(III) octaethylporphyrin which lacks acid groups in its side-chains and has less solution heterogeneity as indicated by absorption and MCD spectroscopies. The propionic acid side chains of protoporphyrin IX are implicated in all such interactions of PPIX, and both dynamic metal-propionic interactions and the formation of propionate-bridged dimers are observed. Fluoride coordination provides an unusual example of slow ligand exchange, and this allows for the identification of a fluoride bridged dimer in solution. An improved synthesis of the chloride and hydroxide complexes of gallium(III) protoporphyrin IX is reported. An insoluble gallium analogue of hematin anhydride is described. In general, the interactions between solvent and the metal are found to confer very high solubility, making [Ga(PPIX)] + a useful model for ferric heme species.
Peacock, R. D.,Selig, H.,Sheft, I.
, p. 2561 - 2561 (1966)
Synthesis of Monosubstituted Trifluoromethylated Derivatives of 2H-thiete, Dihydrothiophenes, and 2H-thiopyrans
Siryi, Serhii A.,Тimoshenko, Vadim М.,Rudenko, Tymofii V.,Markitanov, Yuriy M.,Rusanov, Eduard B.,Shermolovich, Yuriy G.
, p. 106 - 115 (2022/04/03)
[Figure not available: see fulltext.] Cyclic keto sulfides (thietan-3-one, tetrahydrothiophen-3-one, γ-thiobutyrolactone, δ-thiovalerolactone, thiopyran-3-one, and thiopyran-4-one) react with trifluoromethyltrimethylsilane (Ruppert–Prakash reagent) to aff
XeOF3-, an example of an AX3YE2 valence shell electron pair repulsion arrangement; Syntheses and structural characterizations of [M][XeOF3] (M = Cs, N(CH3) 4)
Brock, David S.,Mercier, Helene P. A.,Schrobilgen, Gary J.
, p. 10935 - 10943 (2010/09/16)
The XeOF3- anion has been synthesized as its Cs + and N(CH3)4+ salts and structurally characterized in the solid state by low-temperature Raman spectroscopy and quantum-chemical calculations. Vibrational frequency assignments for [Cs][XeOF3] and [N(CH3) 4][XeOF3] were aided by 18O enrichment. The calculated anion geometry is based on a square planar AX3YE 2 valence-shell electron-pair repulsion arrangement with the longest Xe-F bond trans to the oxygen atom. The F-Xe-F angle is bent away from the oxygen atom to accommodate the greater spatial requirement of the oxygen double bond domain. The experimental vibrational frequencies and trends in their isotopic shifts are reproduced by the calculated gas-phase frequencies at several levels of theory. The XeOF3- anion of the Cs + salt is fluorine-bridged in the solid state, whereas the anion of the N(CH3)4+ salt has been shown to best approximate the gas-phase anion. Although [Cs][XeOF3] and [N(CH 3)4][XeOF3] are shock-sensitive explosives, the decomposition pathways for the anions have been inferred from their decomposition products at 20°C. The latter consist of XeF2, [Cs][XeO2F3], and [N(CH3)4][F]. Enthalpies and Gibbs free energies of reaction obtained from Born-Fajans-Haber thermochemical cycles support the proposed decomposition pathways and show that both disproportionation to XeF2, [Cs][XeO2F3], and CsF and reduction to XeF2, CsF, and O2 are favorable for [Cs][XeOF3], while only reduction to XeF2 accompanied by [N(CH3)4][F] and O2 formation are favorable for [N(CH3)4][XeOF3]. In all cases, the decomposition pathways are dominated by the lattice enthalpies of the products.
