Analytical potential of valence state and ligand atom effects in titanium K X-ray spectra

The Analyst ◽  
1983 ◽  
Vol 108 (1293) ◽  
pp. 1477 ◽  
Author(s):  
John B. Jones ◽  
David S. Urch
Keyword(s):  
Valence State ◽  
X Ray ◽  
Ligand Atom ◽  
Analytical Potential

Monoolefincobalt(0)-Komplexe / Monoolefincobalt(0) Complexes

1988 ◽  
Vol 43 (10) ◽  
pp. 1256-1262 ◽  
Author(s):  
Hans-Friedrich Klein ◽  
Goetz Lull ◽  
Birgit Rodenhäuser ◽  
Gerhard Cordier ◽  
Helmut Paulus
Keyword(s):  
Crystal Structure ◽  
Carbon Monoxide ◽  
Valence State ◽  
Cobalt Atom ◽  
Spectroscopic Properties ◽  
X Ray ◽  
Mononuclear Cobalt ◽  
Structure Determinations

Mononuclear cobalt(o) complexes containing olefin and trimethylphosphane ligands Co(olefin)(PMe3)3 (olefin = C2H4 (1), C3H6 (2), cyclopentene (3), trans-1,2-diphenylethene (4), tetrafluorobenzo-bicyclo-(2.2.2)-octadiene (5)), are obtained from CoCl2 by reaction with magnesium in the presence of the ligands or by substitution of 3 with olefin. X-ray crystal structure determinations of 4 and 5 show a distorted tetrahedral arrangement of ligands around the cobalt atom. Chemical and spectroscopic properties are consistent with a paramagnetic valence state of the compounds in solution. By reaction with carbon monoxide a dicobalt complex is formed, while azobenzene gives paramagnetic Co(N2Ph2)(PMe3)2.

scholarly journals Valence state fossils in Proterozoic stromatolites by L-edge X-ray absorption spectroscopy

2007 ◽  
Vol 112 (G3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Stephen J. Brotton ◽  
Russell Shapiro ◽  
Gerrit van der Laan ◽  
Jinghua Guo ◽  
Per-Anders Glans ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Valence State ◽  
X Ray ◽  
X Ray Absorption

Some X-Ray Observations on the Oxidation Characteristics of Binary Niobium Alloys

1958 ◽  
Vol 2 ◽  
pp. 71-77
Author(s):  
Ralph H. Hiltz
Keyword(s):  
Oxidation Resistance ◽  
Valence State ◽  
Oxidation Rate ◽  
Definite Description ◽  
Substantial Improvement ◽  
Niobium Alloys ◽  
X Ray ◽  
Pure Niobium ◽  
Oxidation Characteristics ◽  
Ionic Size

AbstractPresent knowledge of the effect of alloying on the oxidation characteristics of niobium is limited almost entirely to oxidation rate and oxygen diffusion rate data. In an effort to determine the mechanism by which alloying elements increase or decrease the oxidation rate of niobium, an x-ray study of niobium alloys was performed. Both x-ray diffraction and fluorescent studies were conducted on the base metal before and after oxidation, on the scale formed, and on the interface between the metal and the scale. From the data obtained, a definite description of the mechanism was not possible, but it appears that the Nb0 film between the metal and the Nb203 scale is the rate controlling factor. The elements Ti, Mo, Cr, W, and V which produce a substantial improvement in oxidation resistance effect the formation of a second oxide structure within the Nb0 film. All the elements which provide a measurable increase in oxidation have either a similar ionic size or a +3 valence state and in most cases have both. Elements not having a +3 valence state or similar ionic size, i.e., Cu, Mn, Si, and Zr, do not improve oxidation resistance, in fact Si and Zr act to eliminate the Nb0 film and the oxidation rate of these alloys is greater than pure niobium.

Diolefincobalt(0)-Komplexe / Diolefincobalt(0) Complexes

1984 ◽  
Vol 39 (5) ◽  
pp. 643-648 ◽  
Author(s):  
Hans-Friedrich Klein ◽  
Joachim Groß ◽  
Hubert Witty ◽  
Dietmar Neugebauer
Keyword(s):  
Crystal Structure ◽  
Structure Determination ◽  
Valence State ◽  
Cobalt Atom ◽  
Spectroscopic Properties ◽  
Dinuclear Complex ◽  
X Ray ◽  
Linear Dimer ◽  
Mononuclear Cobalt

Mononuclear cobalt(0) complexes containing diolefin and trimethylphosphane ligands Co(cycloocta-1,5-diene)(PMe3)2 and Co[(CH2=CHMe2Si)2O](PMe3)2 are obtained from CoCl2 by reaction with magnesium in the presence of the ligands or by substitution of cobalt(olefin)tris- (trimethylphosphane) with diolefin. Chemical and spectroscopic properties confirm the para- magnetic valence state of the compounds in solution. An X-Ray crystal structure determination of Co[(CH2=CHMe2Si)2O](PMe3)2 shows a tetrahedral arrangement of ligand functions around the cobalt atom. With butadiene a diamagnetic dinuclear complex [Co(C4H6)(PMe3)3]2 is obtained containing π-allyl co-ordination of two Co(PMe3)3 units to a linear dimer of butadiene

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