Gas Phase Chromatography of Metal Chelates of Acetylacetone, Trifluoroacetylacetone, and Hexafluoroacetylacetone

Abstract

Gas Phase Chromatography of Metal Chelates 693 osmium are increased in contradiction to Pauling's principle. This indicates unequivocally the importance of the -character of Ir-Cl and Os-Cl bonds.Although the present discussion is open to criticism as to the adequacy of the assumed extent of s character of sp hybridized orbitals, the extent of -character of Os-Cl bonds in a hexachloroosmate(IV) ion, etc., the present authors believe that at least an interpretation is presented which is consistent with the experimental data obtained and assumptions made and can throw light upon some phases of the problem of the nature of metal-halogen bonds in complexes.

Gas chemical investigation of hafnium and zirconium complexes with hexafluoroacetylacetone using preseparated short-lived radioisotopes

“…They were produced by vacuum deposition from a resistively heated source. Table 1 lists the properties of the used targets along with the EVRs of interest produced in complete fusion reactions with the 18 O beams (targets #1 and #2) and 50 Ti beams (#3 to #6). Hereafter, the targets are referred to according to their entry in column 1 in Table 1.…”

“…M(hfa) 4 (M = Zr, Hf) are well known complexes [48] and have been investigated with respect to their usefulness as precursors for thin oxide film production of these metals [48]. Zr(hfa) 4 is thermally stable (unlike Zr(tfa) 4 and Zr(acac) 4 [49]) and often employed in gas chromatography studies [50]. The M(hfa) 4 complexes of Zr and Hf are also very similar in other chemical properties [48]: i) both are moisture sensitive, ii) they cannot be separated by gas chromatography owing to their very similar volatility, iii) thermogravimetric analysis (TGA) experiments gave indications for partial decomposition at 146-147…”

“…The nuclear reaction was 50 Ti + 124 Sn (target #5) to produce 169 Hf. The He flow rate in these experiments was 1.5 L/min, T R was 218…”

The Development of a New Kinetic Spectrophotometric Method for the Determination of Vanadium(V) Based on its Catalytic Effect on the Oxidation of Malachite Green Oxalate by Bromate in Acidic and Micellar Medium

“…This metal is widely distributed in the earth's crust but in low abundance.Major sources for the emission of vanadium in the environment include combustion of fuel oils, dyeing, ceramics, ink, catalyst and steel manufacturing.Vanadium in trace amounts represents an essential element for normal cell growth, but it can be toxic when present in higher concentrations 7 . A variety of methods have been used for determination of vanadium; these include fluorometry 8 , gaschromatography 9 , neutron activation analysis 10,11 , x-ray fluorescence spectrometry 12 , emission spectroscopy 13 and atomic absorption spectroscopy 14 kinetic method 15 . These methods either lack sufficient sensitivity or are time consuming.…”

Determination of Free Hydrogen Fluoride in Nonvolatile Metal Fluorides by Gas--Liquid Phase Chromatography.

“…Gas-liquid phase chromatography (GLC) provides a simple, direct method for qualitatively identifying and quantitatively determining volatile constituents in solid inorganic materials (3,4). Theoretically, GLC techniques could be applied to the direct quantitative measurement of free hydrogen fluoride in uranium tetrafluoride and plutonium tetrafluoride, as well as in other nonvolatile inorganic fluorides.…”