Ligand field spectroscopy and chemical bonding in Cr3+-, Fe3+-, Co2+- and Ni2+-containing oxidic solids

Lenglet, M.

doi:10.1016/s0025-5408(00)00243-9

Cited by 13 publications

(8 citation statements)

References 40 publications

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“…Since then, various methods besides ultraviolet (UV) probe ion spectroscopy have been used to obtain OB values for constituent oxides, including such various considerations as electron density, electronegativity, energy gap, refractive index, thermochemical properties, and extraction capacities (sulfur, vanadium, phosphorus), to name a few (Iwamoto et al 1984, Bergman 1988, Duffy 1986aand 1986b. OB has since been shown to have great predictive power for correlating trends in transport properties, including viscosity, electrical and thermal conductivity, and diffusion (Mills 1993 andMitchel et al 1997), thermochemical properties such as heats of formation and thermodynamic activity coefficients (Duffy 2004 andBeckett 2002), and even magnetic (Lenglet 2000) and catalytic properties (Bordes 2000 andMoriceau et al 2000). Reynolds (2006) correlated the OB of glass forming tetrahedra with their influence on waste glass PCT.…”

Section: Overview Of Optical Basicitymentioning

confidence: 99%

Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling

McCloy

Vienna²

2010

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Recent analyses of glass mass estimates from Hanford high-level waste (HLW) performed by the Washington River Protections Solutions (LLC) have shown a strong dependency on the allowable concentrations of Aluminum, Sulfur, Phosphorous, and Bismuth plus the constraint to avoid the precipitation of nepheline from glass. A review was made on the limits for these constraints and it was found that some of them may be overly conservative. Recommendations were made to relax some of the constraints to better estimate the amount of glass likely to be produced from Hanford HLW without significantly increasing the risk of overestimating waste loadings. These changes were made for the Sulfur, Phosphorous, and Bismuth concentration limits along with their basis. In addition, a new nepheline constraint based on glass optical basicity was recommended to help obtain higher alumina concentrations in glass without the formation of nepheline, which generally reduces glasses chemical durability. These recommendations enable continued Hanford live cycle waste treatment modeling until sufficient glass property data and models are generated. The generation of these glass data and models is an on-going, long-term technical need.

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Section: Overview Of Optical Basicitymentioning

confidence: 99%

Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling

McCloy

Vienna²

2010

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“…Examples of correlations of ICP with spectroscopic properties of transition metal oxides were proposed by Lenglet [17,18].…”

Section: Scale Of Optical Basicity Of Solid Oxidesmentioning

confidence: 99%

Multicomponent Oxides in Selective Oxidation of Alkanes Theoretical Acidity versus Selectivity

Bordes‐Richard

2008

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Semi-empirical relationships between the 'optical basicity' K (so-called after Duffy) of solid oxides and the 'thermodynamic' selectivity in mild and total oxidation of hydrocarbons have recently been set up. They can be used to determine the optimum acidity of a solid catalyst or to account for its observed selectivity in a given reaction. The oxidic M x O z catalysts were ranked by means of the electron-donor power of oxygen which is represented by the optical basicity K. The difference of ionization potential I of molecules when the reactant becomes the product, which represents the variation of electron-donor power during the reaction, was used to rank reactions. Plotting DI against K for each 'reaction/selective catalyst' couple results in straight lines, the equation of which depends on the chemical nature of reactant (alkane and alkyl-aromatics, alkenes and aromatics, alcohols) and on the deepness of oxidation (ammoxidation, mild oxidation, total oxidation). The correlations are used to discuss the behaviour of V-and Mo-based, simple and multicomponent oxide catalysts, in the mild oxidation of C 2 and C 3 hydrocarbons.

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“…Optical basicity concepts have been applied to understand and predict the refractivity of glasses, 9,10 nonlinear optical properties, 11 the reduction–oxidation of cations, 12–14 the behavior of extractive metallurgical slags, 15–18 and even the behavior of catalysts 19 . Optical basicity has been shown to be closely related to parameters describing the chemical bonding in oxides, including electronic polarizability of oxygen, EN (variously conceived), 20,21 the Racah parameters, 12,14,22 the energy gap, 20 and the oxygen‐binding energy 23 …”

Section: Optical Basicitymentioning

confidence: 99%

The Predictive Power of Electronic Polarizability for Tailoring the Refractivity of High‐Index Glasses: Optical Basicity Versus the Single Oscillator Model

McCloy

Riley

Johnson

et al. 2010

Journal of the American Ceramic Society

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High‐density (∼8 g/cm3) heavy metal oxide glasses composed of PbO, Bi2O3, and Ga2O3 were produced, and refractivity parameters (refractive index and density) were computed and measured. Refractive indices were measured at six discrete wavelengths from 0.633 to 10.59 μm using a prism coupler, and data were fitted to the Sellmeier expression. Optical basicity was computed using three models—average electronegativity, ionic‐covalent parameter, and energy gap—and the results were used to compute oxygen polarizability and subsequently the refractive index. Single oscillator energy and dispersion energy were calculated from experimental indices and from oxide energy parameters. The predicted glass index dispersion based on oxide oscillator parameters underestimates the measured index by only 3%–4%. The predicted glass index from optical basicity, based on oxide energy gaps, underpredicts the index at 0.633 μm by only 2%. The calculated glass energy gap based on this optical basicity overpredicts the experimental optical gap by 6%–10%. Thus, we have shown that the density, the refractive index in the visible, and the energy gap can be reasonably predicted using only composition, optical basicity values for the constituent oxides, and partial molar volume coefficients. The relative contributions of the oxides to the total polarizability were assessed, providing an additional insight into controlling the refractivity of high‐index glasses.

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Ligand field spectroscopy and chemical bonding in Cr3+-, Fe3+-, Co2+- and Ni2+-containing oxidic solids

Cited by 13 publications

References 40 publications

Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling

Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling

Multicomponent Oxides in Selective Oxidation of Alkanes Theoretical Acidity versus Selectivity

The Predictive Power of Electronic Polarizability for Tailoring the Refractivity of High‐Index Glasses: Optical Basicity Versus the Single Oscillator Model

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