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Inorganic Chemistry Commons™

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2002

Articles 1 - 8 of 8

Full-Text Articles in Inorganic Chemistry

Hplc Of Monolayer-Protected Gold Nanoclusters, Victoria L. Jimenez,, Michael C. Leopold, Carolyn Mazzitelli, James W. Jorgenson, Royce W. Murray Dec 2002

Hplc Of Monolayer-Protected Gold Nanoclusters, Victoria L. Jimenez,, Michael C. Leopold, Carolyn Mazzitelli, James W. Jorgenson, Royce W. Murray

Chemistry Faculty Publications

Polydisperse samples of Au nanoparticles protected with monolayers of hexanethiolate ligands (C6 MPCs) and with mixed monolayers of hexanethiolate and mercaptounde- canoic acid (C6/MUA MPCs) have been chromatographically separated using C8 120-Å columns and acetone/toluene mobile phase. The spectral details of eluted peaks and of quantized double-layer charging features in the differential pulse voltammetry of collected fractions were used to show that the elution orders of C6 MPC mixtures and of C6/MUA MPC mixtures were different. For C6 MPCs, the smallest MPCs were eluted first, whereas the smallest C6/MUA MPCs were eluted last. The reversal of order of elution was …

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Non-Dipolar Electron Angular Distributions From Fixed-In-Space Molecules, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, E. Shigemasa, K. Le Guen, D. Ceolin, C. Miron, N. Leclercq, P. Morin, Marc Simon, P. W. Langhoff Jul 2002

Non-Dipolar Electron Angular Distributions From Fixed-In-Space Molecules, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, E. Shigemasa, K. Le Guen, D. Ceolin, C. Miron, N. Leclercq, P. Morin, Marc Simon, P. W. Langhoff

Environmental Studies Faculty Publications

The first indication of nondipole effects in the azimuthal dependence of photoelectron angular distributions emitted from fixed-in-space molecules is demonstrated in N2. Comparison of the results with angular distributions observed for randomly oriented molecules and theoretical derivations for the nondipole correction first order in photon momentum suggests that higher orders will be needed to describe distributions measured in the molecular frame.

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Electron Hopping Conductivity And Vapor Sensing Properties Of Flexible Network Polymer Films Of Metal Nanoparticles, Francis P. Zamborini, Michael C. Leopold, Jocelyn F. Hicks, Pawel J. Kulesza, Marcin A. Malik, Royce W. Murray Jun 2002

Electron Hopping Conductivity And Vapor Sensing Properties Of Flexible Network Polymer Films Of Metal Nanoparticles, Francis P. Zamborini, Michael C. Leopold, Jocelyn F. Hicks, Pawel J. Kulesza, Marcin A. Malik, Royce W. Murray

Chemistry Faculty Publications

Films of monolayer protected Au clusters (MPCs) with mixed alkanethiolate and ω-carboxylate alkanethiolate monolayers, linked together in a network polymer by carboxylate-Cu2+-carboxylate bridges, exhibit electronic conductivities (σEL) that vary with both the numbers of methylene segments in the ligands and the bathing medium (N2, liquid or vapor). A chainlength-dependent swelling/contraction of the film's internal structure is shown to account for changes in σEL. The linker chains appear to have sufficient flexibility to collapse and fold with varied degrees of film swelling or dryness. Conductivity is most influenced (exponentially dependent) by the chainlength of the nonlinker (alkanethiolate) ligands, a result consistent …

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Photoexcitation Of A Dipole-Forbidden Resonance In Helium, B. Krassig, E. P. Kanter, S. H. Southworth, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, R. Wehlitz, N. L. S. Martin May 2002

Photoexcitation Of A Dipole-Forbidden Resonance In Helium, B. Krassig, E. P. Kanter, S. H. Southworth, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, R. Wehlitz, N. L. S. Martin

Environmental Studies Faculty Publications

We have observed photoexcitation of the dipole-forbidden 1s21S0→2p21D2 resonance in helium by measuring the nondipolar forward-backward asymmetry of photoelectron angular distributions in the 2ℓ2ℓ′ autoionizing region. By exploiting the electric dipole-quadrupole interference in the excitation of both the 2s2p1P1 and 2p21D2 levels, we have observed the quadrupole resonance in photoabsorption and extracted its Fano line shape parameters and the relative phase of the 1sEp and 1sEd continua. We find the quadrupole line profile index q2 to be markedly different from theoretical expectations.

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The Influence Of Gold Substrate Topography On The Voltammetry Of Cytochrome C Adsorbed On Carboxylic Acid Terminated Self-Assembled Monolayers, Michael C. Leopold, Edmond F. Bowden Feb 2002

The Influence Of Gold Substrate Topography On The Voltammetry Of Cytochrome C Adsorbed On Carboxylic Acid Terminated Self-Assembled Monolayers, Michael C. Leopold, Edmond F. Bowden

Chemistry Faculty Publications

Interfacial investigations of a protein monolayer electrochemical system, equine cytochrome c (cyt c) adsorbed to carboxylic acid terminated self-assembled monolayer (COOH SAM) modified gold electrodes, were performed. Electrochemical, spectroscopic, and scanning probe microscopy techniques were utilized to explore the influence of gold topography in the cyt c/COOH SAM/gold system. COOH SAMs were prepared from 14-mercaptotetradecanoic acid and 11-mercaptoundecanoic acid on a variety of substrates including evaporated, bulk, single crystal, and epitaxially grown gold on mica. These substrates encompassed a wide range of surface roughness. As the topography of the gold became smoother, SAMs exhibited an increased ability to …

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An On-Line Acid-Base Titration Applet In The Generic Tutorial System For The Sciences Project, Thomas Lee Gummo Jan 2002

An On-Line Acid-Base Titration Applet In The Generic Tutorial System For The Sciences Project, Thomas Lee Gummo

Theses Digitization Project

The purpose of this Master's Project was to develop an Acid-Base Titration Simulator. It was also to be a part of the California State University - San Bernardino's GTSS, Generic Tutorial System for the Sciences, project. The main benefit is that students will be able to conduct titration experiments over the Internet without being in the laboratory and without costly equipment or dangerous chemicals. Instructors at the high school and college level can demonstrate the key principles of titration.

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Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean Jan 2002

Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean

Chemistry Faculty Research & Creative Works

The complex {Fe [HC(3,5-Me2pz)3]2} I2 (1) has been prepared from the reaction of FeI2 and HC(3,5-Me2pz)3 (pz = pyrazolyl ring) in a 1:2 ratio. The complex is high spin in both the solid state and in solution at ambient temperature. In the solid state, magnetic susceptibility and Mössbauer spectral studies indicate that samples of the complex that have been crystallized and dried change completely from high-spin to low-spin upon cooling below 195 K, with a substantial two-step thermal hysteresis in the transition. The spin-crossover properties of 1 are sample …

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Adsorptive Immobilization Of Cytochrome C On Indium/Tin Oxide (Ito): Electrochemical Evidence For Electron Transfer-Induced Conformational Changes, Asma El Kasmi, Michael C. Leopold, Ryan Galligan, Rebecca T. Robertson, S. Scott Saavedra, Kacem El Kacemi, Edmond F. Bowden Jan 2002

Adsorptive Immobilization Of Cytochrome C On Indium/Tin Oxide (Ito): Electrochemical Evidence For Electron Transfer-Induced Conformational Changes, Asma El Kasmi, Michael C. Leopold, Ryan Galligan, Rebecca T. Robertson, S. Scott Saavedra, Kacem El Kacemi, Edmond F. Bowden

Chemistry Faculty Publications

The adsorptive immobilization and electrochemistry of horse and yeast cytochrome c on indium/tin oxide (ITO) electrodes is reported. Near-monolayer coverage was achieved in pH 7 phosphate buffers of ionic strength equal to 10 and 50 mM, respectively, for the horse and yeast species. The layers exhibit very well-behaved voltammetry and are stable on the timescale of hours to days. Cyclic voltammetry revealed quasireversible behavior that is a product of both electron transfer (ET) kinetics and ET-induced conformational changes. A square scheme mechanism linking the redox states and the conformational states is proposed. Using a simple ET kinetic model that adequately …

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