Publisher Summary This chapter discusses the characterization and reactivity of mononuclear oxygen species on oxide surfaces. Measurement of the electron paramagnetic resonance (EPR) parameters gives information which at the simplest level indicates the presence of a paramagnetic species but which can be sufficiently detailed to identify and characterize the adsorbed species. Measurements of the variation of the intensity of the signal with time can give kinetic data on reactions occurring at the surface. Although most of the EPR measurements have been carried out at low temperatures, there is evidence from the examples for some of the species that are stable at much higher temperatures and may play an important role in catalytic reactions.

Characterization and Reactivity of Molecular Oxygen Species on Oxide Surfaces

Quasi-solid-state dye-sensitized solar cells were fabricated using low-molecular-weight gelators. They showed comparable photoenergy conversion efficiencies to the liquid cell at high illumination intensity up to AM 1.5 (1 sun). Conductivity measurements of the electrolyte phases revealed that the gelation does not affect the conductivity of the electrolyte and that the conductivity increased with an increase of iodine in both gel electrolytes and liquid electrolyte. The formation of polyiodide ions, such as I3- and I5-, caused by addition of iodine was confirmed by Raman spectroscopic measurement. The self-diffusion of iodide species in the gel electrolyte was found about a quarter of that of I- in acetonitrile. The formation of less-mobile polyiodide ions in electrolyte increased the conductivity in the mesoporous phase, which should be rationalized as due to the Grotthuss-type electron exchange mechanism caused by rather packed polyiodide species in the electrolytes. The optimized quasi-solid-state cel...

Quasi-Solid-State Dye-Sensitized TiO2 Solar Cells: Effective Charge Transport in Mesoporous Space Filled with Gel Electrolytes Containing Iodide and Iodine

3.1. Sc Group 6772 3.2. Ti Group 6773 3.3. V Group 6775 3.4. Cr Group 6776 3.5. Mn Group 6777 3.6. Fe Group 6779 3.7. Co Group 6780 3.8. Ni Group 6782 3.9. Cu Group 6782 3.10. Zn Group 6784 3.11. Lanthanide Group 6784 3.12. Actinide Group 6785 3.13. Periodic Trends on Bonding and Reactivity 6785 4. Ionic Mononuclear Transition Metal Oxide Species 6787 4.1. Cations 6788 4.2. Anions 6790 4.2.1. Monoxide Anions 6790 4.2.2. Dioxide Anions 6791 4.2.3. Oxygen-Rich Anions 6792 5. Multinuclear Transition Metal Oxide Clusters 6792 5.1. Sc Group 6793 5.2. Ti Group 6793 5.3. V Group 6793 5.4. Cr Group 6797 5.5. Mn Group 6798 5.6. Fe Group 6798 5.7. Co Group 6798 5.8. Ni Group 6798 5.9. Cu Group 6799 6. Summary 6800 7. Acknowledgments 6800 8. References 6800

Spectroscopic and theoretical studies of transition metal oxides and dioxygen complexes.

Ozone is a unique species whose chemistry has a profound impact in many areas of our society. It is well known as a beneficial constituent of the upper atmosphere which shields living organisms fro...

Chemical and Catalytic Properties of Ozone

Resonance Raman spectra are obtained when the wave number of the exciting radiation is close to, or coincident with, that of an electronic transition of the scattering species. Such spectra are usually characterized by a very large enhancement of the intensities of particular Raman bands, sometimes with the appearance of intense overtone and combination tone progressions. The technique provides detailed information about excited electronic states because it is only the vibrational modes associated with the chromophore that are resonance-Raman active. Additionally, the high sensitivity is such that compounds at concentrations as low as 10−6 mol/L may be detected, enabling resonance Raman spectroscopy to be used as an analytical tool and for the study of chromophores in molecules of biological interest.

Resonance Raman Spectroscopy, and Its Application to Inorganic Chemistry. New Analytical Methods (27)

Resonance Raman and ultraviolet absorption spectra of the triiodide ion produced by alkali iodide-iodine argon matrix reactions

The magnesium–ozone reaction has been studied by condensing the reagents with nitrogen at 14 K. Isotopic substitution with 26Mg, 16,18O3, and 18O3 has identified infrared absorptions due to two different Mg+O−3 species, MgO2 and MgO. Six isotopic MgO molecules support this infrared detection of MgO which shows a blue matrix shift. Analogous argon matrix reactions produced only Mg+O−3 and two isomeric MgO3 species.

Matrix reactions of magnesium atoms with ozone. Infrared spectra of MgO, MgO2, and MgO3 in solid nitrogen

Reactions of zinc and cadmium atoms with ozone during condensation with excess nitrogen or argon produced B+O3− ion‐pairs having infrared, Raman, and optical spectra similar to the analogous alkali and alkaline earth metal species. Additional infrared and Raman evidence was found for a different B+O3− ion‐pair geometry. Mercury arc photolysis reduced ozonide absorptions and produced new 810 cm−1 zinc isotopic triplets which showed the appropriate 18O shifts for ZnO, and a new 719 cm−1 band which showed the proper 18O displacement for CdO. This nitrogen matrix work provides good measures of the yet‐to‐be‐observed gas‐phase fundamentals of these high temperature oxides.

Infrared, Raman, and visible spectroscopic studies of Zn and Cd matrix reactions with ozone. Spectra of metal ozonides and oxides in solid argon and nitrogen

Raman, infrared and ultraviolet spectra of the chlorine difluoride free radical in solid nitrogen

Matrix photoionization of methyl halides. Ultraviolet spectra of the parent cations and infrared evidence for intramolecular hydrogen-bonded parent anions in solid argon

Eleanor S. Prochaska

Papers

Resonance Raman and ultraviolet absorption spectra of the triiodide ion produced by alkali iodide-iodine argon matrix reactions

Matrix reactions of magnesium atoms with ozone. Infrared spectra of MgO, MgO2, and MgO3 in solid nitrogen

Infrared, Raman, and visible spectroscopic studies of Zn and Cd matrix reactions with ozone. Spectra of metal ozonides and oxides in solid argon and nitrogen

Raman, infrared and ultraviolet spectra of the chlorine difluoride free radical in solid nitrogen

Matrix photoionization of methyl halides. Ultraviolet spectra of the parent cations and infrared evidence for intramolecular hydrogen-bonded parent anions in solid argon