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Showing 1 to 17 of 17 for “"Covalency"”.

  1. Advancing solvent extraction technology for improved management of contaminated liquors

    … to investigate the structure, stabilities and covalency of complexes of the lanthanides and minor actinides with several nitrogen donor ligands which have been developed for the difficult task of AnIII/LnIII separation. A systematic QTAIM study of Ln bond characterisation across the series is …

    lancaster Repository record for Advancing solvent extraction technology for improved management of contaminated liquors (opens in a new tab)

  2. Interplay between electronic structure and catalytic activity in transition metal oxide model system

    … the extent of B-site transition metal-oxygen covalency can serve as a secondary activity descriptor. We hypothesize that this correlation reflects the critical influences of the a* orbital and transition metal-oxygen covalency on the ability of the surface to displace and stabilize …

    mit Repository record for Interplay between electronic structure and catalytic activity in transition metal oxide model system (opens in a new tab)

  3. The Intensity of Ligand Absorption

    … metal ion in the complex. Since the degree of covalency depends on the degree of back donation, the oxidation state of the metal ion was found to be the most important factor in determining the intensity of the absorption. The more covalent the metal-phosphine bond, the lower is the intensity …

    wku-diss Repository record for The Intensity of Ligand Absorption (opens in a new tab)

  4. Transuranic Imidophosphorane Chemistry

    … we demonstrate PCET reactivity as a measure of covalency for this imidophosphorane family.

    gatech Repository record for Transuranic Imidophosphorane Chemistry (opens in a new tab)

  5. Lanthanide-based single-molecule magnets: A rational design by chemical intuition

    … for Dy2 to gain insight on the contribution of covalency, crystal field effect and the role of aromaticity in stabilizing the excited magnetic levels of a single-molecule magnet. Dy1 showed frequency-dependent slow magnetic relaxation characteristics of a single-molecule magnet with and without …

    cambridge Repository record for Lanthanide-based single-molecule magnets: A rational design by chemical intuition (opens in a new tab)

  6. Developing Telecom Band-Compatible Molecular Color Centers for Quantum Networking

    … and controlled increase of metal-ligand bonding covalency. This strategy culminates in a series of V_III complexes which tune emission wavelength from 1237 nm to 1424 nm, achieving emission into the telecom band. Chapter 4 will discuss the impact of these strategies on the magnetic properties and …

    mit Repository record for Developing Telecom Band-Compatible Molecular Color Centers for Quantum Networking (opens in a new tab)

  7. The Interplay Between Anions And Radicals In Synthesis, Spectroscopy, And Catalysis

    … that the CeIV–Caryl bond displayed significant covalency. The use of the TiCl62- dianion towards photolytic C–H functionalization of hydrocarbons is also described. The photo-reactivity of TiCl62- allows for the activation of hydrocarbons, including methane. Mechanistic investigations, including …

    penn Repository record for The Interplay Between Anions And Radicals In Synthesis, Spectroscopy, And Catalysis (opens in a new tab)

  8. Understanding and Controlling the Degradation of Nickel-rich Lithium-ion Layered Cathodes

    … oxygen by limiting the nickel and oxygen covalency that typically leads to oxygen activation upon charging. We observed that the titanium substitution increases cycling reversibility after hundreds of cycles. Overall, the work indicates that a more stable nickel-rich material is possible. …

    vt Repository record for Understanding and Controlling the Degradation of Nickel-rich Lithium-ion Layered Cathodes (opens in a new tab)

  9. Exploring transition metal chalcogenides for bio sensing and environmental remediation

    … on the transition metal site as well as enhanced covalency in the lattice due to the low anion electronegativity. To examine this theory, CoNi<sub>2</sub>Se<sub>4</sub> is studied for its application in full water splitting. This catalyst shows an excellent electrocatalytic activity with low …

    must-thes Repository record for Exploring transition metal chalcogenides for bio sensing and environmental remediation (opens in a new tab)

  10. Theoretical study of polar complex oxide heterostructures

    … the formal charges of the ions, irrespective of covalency, and despite both materials being centrosymmetric. The interfacial net charge, or equivalently the LAO formal polarisation, requires charge screening which calculations show can be possible via an electronic transfer between neighbouring …

    cambridge Repository record for Theoretical study of polar complex oxide heterostructures (opens in a new tab)

  11. Purely ionic and molecular orbital modelings of the bonding in mineral crystal structures

    … may illustrate the significance of CO bond covalency in determining the physico-chemical properties of CaCO₃. The MEG model has also been used to generate model alkali halide crystals in the sphalerite, rocksalt, and CsCl types in an exploration of the reliability of the radius ratio rule. …

    vt Repository record for Purely ionic and molecular orbital modelings of the bonding in mineral crystal structures (opens in a new tab)

  12. Fundamental Investigations of Mechanistic Pathways of Selected Organic Reactive Intermediates

    … used the excess tc-electron density for greater covalency in the complex. In Part 2, the gas-phase reaction between the ethylene oxide radical cation and neutral ethylene oxide, when performed in the high-pressure source of a tandem mass spectrometer, forms a C4Hg02 radical cation adduct. The …

    wku-diss Repository record for Fundamental Investigations of Mechanistic Pathways of Selected Organic Reactive Intermediates (opens in a new tab)

  13. Fundamental magnetic properties of Greigite (Fe3S4)

    … is probably caused by an increased degree of covalency between iron and sulphur compared to oxygen ligands, and/or by greater delocalization of the 3d electrons. By measuring the low-temperature Ms of pure greigite samples and based on the Bloch spin wave expansion, the spin wave stiffness of …

    soton Repository record for Fundamental magnetic properties of Greigite (Fe3S4) (opens in a new tab)

  14. Vibrational and anion photoelectron spectroscopy of transition metal clusters

    … the rare gas atom by proposing some amount of covalency in the bonding. Motivated by the role of ruthenium as catalyst for CO methanation in the Fischer-Tropsch process, the composition and structures of saturated cationic ruthenium carbonyls are studied. Their IR spectra are obtained in the …

    tu-berlin Repository record for Vibrational and anion photoelectron spectroscopy of transition metal clusters (opens in a new tab)

  15. Coordination Chemistry of Fe–S Clusters Supported by N-Heterocyclic Carbenes

    … events. This suggests that Mo may increase the covalency within the cluster, potentially making access to these low valent states more facile. Lastly, we introduce three studies aimed at modelling biological Fe–S cluster chemistry: revealing reversible homolytic Fe–C bond cleavage at Fe–S …

    mit Repository record for Coordination Chemistry of Fe–S Clusters Supported by N-Heterocyclic Carbenes (opens in a new tab)

  16. Crystal chemical design rules for tailored chemical expansivity

    Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-12-01

    uiuc Repository record for Crystal chemical design rules for tailored chemical expansivity (opens in a new tab)