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X-Ray-Absorption Spectral Study Of The R₂Fe₁₇₋ₓmₓ Solid Solutions (R=Ce, Nd And M=Al, Si), Denis Vandormael, Fernande Grandjean, Valérie Briois, D. P. Middleton, K. H. Buschow, Gary J. Long Sep 1997

X-Ray-Absorption Spectral Study Of The R₂Fe₁₇₋ₓmₓ Solid Solutions (R=Ce, Nd And M=Al, Si), Denis Vandormael, Fernande Grandjean, Valérie Briois, D. P. Middleton, K. H. Buschow, Gary J. Long

Chemistry Faculty Research & Creative Works

The x-ray-absorption near-edge structure (XANES) spectra obtained at the cerium LIII edge of the Ce2Fe17-xAlx solid solutions and Ce2Fe14Si3, show two absorption peaks characteristic of the 4f1 and 4f0 configurations of cerium, peaks which indicate that cerium is in a mixed valent state in these compounds. All the XANES spectra have been consistently and excellently fit with one sigmoidal function and two Gaussianbroadened Lorentzian functions. The cerium spectroscopic valence obtained from the relative areas of the two peaks decreases from 3.64 to 3.43 between x=0 and …

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Electrical Potential Distribution Around A Charged Colloidal Particle: Nonlinear Integral Equation, Yongxian Qian, Hao Deng, Guangzheng Yang Aug 1997

Electrical Potential Distribution Around A Charged Colloidal Particle: Nonlinear Integral Equation, Yongxian Qian, Hao Deng, Guangzheng Yang

Journal of Electrochemistry

The electrical potential distribution around a charged colloidal particle in a solution of general electrolytes is governed by the nonlinear Poisson Boltzmann equation, which is a differential equation and difficult to solve analytically. In this paper we numerically calculate the electrical potential using nonlinear Qian Poisson Bolazmann integral equation (PBIE). First, we introduce the PBIE derived from the physical principles for electrostatic fields and thermodynamic systems. Then the PBIE is numerically solved by means of iteration, in which the discrete potential is solely used. Finally, the accuracy of the numerical solutions proposed here is discussed.

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Study On The Diffusion Of Electroactive Molecules In Polymer Electrolyte By Microelectrode Voltammetry, Liming Ding, Shaojun Dong, Erkang Wang Aug 1997

Study On The Diffusion Of Electroactive Molecules In Polymer Electrolyte By Microelectrode Voltammetry, Liming Ding, Shaojun Dong, Erkang Wang

Journal of Electrochemistry

The ten years study on the diffusion of electroactive molecules in polymer electrolyte by microelectrode voltammetry was reviewed by considering the development background of polymer electrolyte materials. The classification, fabrication, applications and electrochemical measurements of microelectrode were introduced concisely. The several important factors influencing the diffusion of electroactive molecules were stressed. In the final part of this paper, some new reports on the diffusion of labeled molecules were introduced.

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Study On Electrochemical Reactions Of K4[Fe(Cn)6]/K3[Fe(Cn)6] With Graze Ellipsometry, Shengtao Zhang, Changyuan Tao, Nianbing Li, Zongqing Huang, Chushao Xu Aug 1997

Study On Electrochemical Reactions Of K4[Fe(Cn)6]/K3[Fe(Cn)6] With Graze Ellipsometry, Shengtao Zhang, Changyuan Tao, Nianbing Li, Zongqing Huang, Chushao Xu

Journal of Electrochemistry

A measurement technology of ellipsometry called graze was put forward. Electrochemical reactions of K4[Fe(CN)6]/K3[Fe(CN)6] on glass electrode deposited indium oxide were studied with both the graze ellipsometry and cycilic voltammetry. The results indicated that ellipsometric parameter and its change during the electrochemical reactions could be confirmed with graze ellipsometry, and the regularity was corresponding to the process of electrochemical reaction. So study for electrode system could be processed with the graze ellipsometry. The graze ellipsometry could also be applied to analyze properties of diffusion layer and prosthesis limitations of other technologies.

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Behavior Of Copper In Hydrogen Storage Alloy Microencapsulated By Copper, Dawei Zhang, Huatang Yuan, Huabin Yang, Zuoxiang Zhou, Yunshi Zhang Aug 1997

Behavior Of Copper In Hydrogen Storage Alloy Microencapsulated By Copper, Dawei Zhang, Huatang Yuan, Huabin Yang, Zuoxiang Zhou, Yunshi Zhang

Journal of Electrochemistry

Negative electrode made from Cu microencapsulated hydrogen storage alloy was studied by using cyclic voltammetry method. The results showed that copper as a coating material was of a certain stability in 5 mol/L KOH solution within the range of charge and discharge voltage. But when expanding the sweep voltage, the CV curve showed a pair of distinct oxidation reduction current peaks of Cu2O formation at E = -0.3 V and Cu2O reduction at E =-0.6 V. With charging discharging cycles, copper is liable to be oxidized to Cu2O and further oxidized into CuO2 …

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Corrosion Behaviour Of Copper Covered With Ion Selective Phenolic Coatings By Eis, Zhoucheng Wang, Yingzhou Zhang, Shaomin Zhou Aug 1997

Corrosion Behaviour Of Copper Covered With Ion Selective Phenolic Coatings By Eis, Zhoucheng Wang, Yingzhou Zhang, Shaomin Zhou

Journal of Electrochemistry

Electrochemical impedance spectroscopy(EIS) technique was employed to study the corrosion behaviour of copper painted with the anion selective, cation selective and bipolar phenolic coatings in 3% NaCl solution. From the impedance spectrum characteristics, the models of equivalent circuit for these different coating systems were established, and the methods for the analysis of experimental impedance diagrams in terms of coating and interface properties were discussed. The research results show that the composition and structure of ion selective coatings have significant influence on corrosion behaviour of copper. The bipolar coating consisting of an anion selective inner layer and a cation selective outer …

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Rechargeability Of Zn-Mno2 In Non-Aqueous Electrolyte, Baoqi Li, Hanxi Yan, Mifang Du, Xinping Ai Aug 1997

Rechargeability Of Zn-Mno2 In Non-Aqueous Electrolyte, Baoqi Li, Hanxi Yan, Mifang Du, Xinping Ai

Journal of Electrochemistry

A novel Zn-MnO2 battery ststem by use of spinel related MnO2 as positive electrode and Zn(ClO4)2 in propyl carbonate as electrolyte was constructed and its charge discharge behaviour was studied. The results show that the cell reaction of the system proceeds through the electrochemical intercalation of zinc into the crystalline lattice of MnO2 to form ZnxMn2O4. At x≤0.5, ZnxMn2O4 onstrates excellent cycleability (>200 cycles), higher discharge charge efficiency (>90%) and prolonged storage life.

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Electrocatalytic Oxidation Of Methanol On The Stearate Nickel L-B Film, Benzeng Hua, Wenyan Hu, Yanzhen Chen, Yanhong Zhang Aug 1997

Electrocatalytic Oxidation Of Methanol On The Stearate Nickel L-B Film, Benzeng Hua, Wenyan Hu, Yanzhen Chen, Yanhong Zhang

Journal of Electrochemistry

The stearate nickel L-B films is good electroacatlyst for the oxidation of methanol MeOH in alkaline. The electrochemical behaviors of stearate nickel L-B films is affected by the concentration of KOH. The rate of quantity of mickel ion and stearic acid in L-B films is 1∶1, which means that the nickel ion may exist in -COONi(OH) form. The electrocatalytic process is influenced by the concentration of OH-, it involves the penetration of MeOH into the films. The oxidative currents of MeOH are linearly dependent on the bulk concentration.

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Study On Electrochemical Methods Of Controlled Convolution ——A Simple Electron Transfer Reaction Followed By A Homogeneous Catalytic Reaction(Ⅰ), Ming Ma, Naixian Xie, Qianlei Gao, Yue Zeng Aug 1997

Study On Electrochemical Methods Of Controlled Convolution ——A Simple Electron Transfer Reaction Followed By A Homogeneous Catalytic Reaction(Ⅰ), Ming Ma, Naixian Xie, Qianlei Gao, Yue Zeng

Journal of Electrochemistry

A simple electron transfer reaction followed by a homogeneous catalytic reaction is studied in this paper by three kinds of controlled convolution electrochemical experimental methods, which are the constant semi integral (CSI), linear semi integral sweep (LSIS) and linear semi differential sweep (LSDS). According to the three methods, the following equations can be obtained. With these equations, the theoretical curves of the above three methods can be computed. Experiments of the ferrocyanide ascorbic acid catalytic system have confirmed that kinetic rate constant in catalytic reaction is in good agreement with the previously reported values.

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Preparation And Examination Of Planar Type Solid Oxide Fuel Cells, Yi Jiang, Jingwang Yan, Shizhong Wang, Chunying Yu, Wenzhao Li Aug 1997

Preparation And Examination Of Planar Type Solid Oxide Fuel Cells, Yi Jiang, Jingwang Yan, Shizhong Wang, Chunying Yu, Wenzhao Li

Journal of Electrochemistry

The solid oxide fuel cells of planar type (SOFC) have been developed after successfully preparing La0.8Sr0.2MnO3 cathodes and Ni-YSZ ceramic anodes on YSZ plates and solving the high temperature sealing technical problem. Examination of the single cells fabricated showed that the maximum power output at 950 ℃ for H2 as fuel and air as oxidant reached 0.12 W/cm2. It was found that the large polarization overpotential of the Ni-YSZ anode and the Ohmic losses of the cells were two main factors responsible for the relative low output power density.

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The Electrode Process Of Some Organic Dyes Studied By Spectroelectrochemical Technique In Situ, Yinxuan Tang, Hangsheng Yang, Baoen Shen Aug 1997

The Electrode Process Of Some Organic Dyes Studied By Spectroelectrochemical Technique In Situ, Yinxuan Tang, Hangsheng Yang, Baoen Shen

Journal of Electrochemistry

Spectroelectrochemistry especially with in situ measurement in a cell provides a very useful mthodology for measuring the parameters of electrode process. In this paper, we report the determination of formal potentials, the number of electron transfer, the diffusion coefficient, the heterogeneous electron transfer rate constant and the transfer coefficient of some organic dyes (Methyelene blue, Neutral red, Indigo carmine) using spectroelectro chemical technique in situ.

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Determination Of Theine And Theinein Aminophylline By Oscillographic Titration, Zhaoren Meng, Yongfu Zhan Aug 1997

Determination Of Theine And Theinein Aminophylline By Oscillographic Titration, Zhaoren Meng, Yongfu Zhan

Journal of Electrochemistry

In this paper, a method is described for the determination of theine and theine in aminophglline by oscillographic titration. The theine or theine in amimophylline and AgNO3 can make precipitation quantitatively. The quantitative and excess AgNO3 is added in it, when reaction has been completed, the residual AgNO3 can be carred out directly by oscillographic titrimetry with DDTC as titrant. Trace DDTC can make a slot on oscillogram of mercury membrane and silver electrodes. Using DDTC standard solution to titrate, that is the slot appearing. It can be used to indicate end point sensitively. The characteristics of …

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Electrorheological Characters Of Polyaniline Suspensions, Guangyao Su, Deshu Gao, Changqing Zhang Aug 1997

Electrorheological Characters Of Polyaniline Suspensions, Guangyao Su, Deshu Gao, Changqing Zhang

Journal of Electrochemistry

Polyaniline (PAn) as the dispersive particles and insulating oil as the dispersive medium, the electrorheological fluid (ERF) is constituted. Relations between the factors of electric field strength (E), temperature (T) and the static yield stress (τS), current density (i) of ERF are investigated. The results show that the changes of τS and i with electric field intensity have emerged in the exponential relation, i.e, τS∝E0.7, i∝E2.18. Otherwise, when exert a constant voltage on ERF, owing to the polarization, the absorption of medium of ERF have taken place. Therefore, the attenuation rate …

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Investigation On Electro Reduction Behaviour Of Copper Anodic Products In Concentrated Naoh Solutions Ⅱ. Electro Reduction Of Cu(Ⅱ) Products, Jianbo He, Hanhe Chen, Jianxin Lin Aug 1997

Investigation On Electro Reduction Behaviour Of Copper Anodic Products In Concentrated Naoh Solutions Ⅱ. Electro Reduction Of Cu(Ⅱ) Products, Jianbo He, Hanhe Chen, Jianxin Lin

Journal of Electrochemistry

Potentiostatic oxidation potentiodynamic or galvanostatic reduction methods have been used to study the cathodic reduction behaviour of various products anodically formed on the second stage of copper oxidation in concentrated NaOH solutions. Seven cathodic current peaks and the corresponding cathodic potential plateaus are observed on the potentiodynamic E/i curves and the galvanostatic E/t curves, respectively. In the negative potential scan, there are three couples of voltammetric peaks which have been attributed to the formation and reduction of CuO, Cu(OH)2 and Cu(Ⅱ) ion, respectively. The complicated mechanism for the electro formation of the three Cu(Ⅱ) species are discussed.

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Preparation Of Pbo2/Ti Plate Electrode, Zhigang Shao, Baolian Yi, Xinge Zhang, Enjun Zhang Aug 1997

Preparation Of Pbo2/Ti Plate Electrode, Zhigang Shao, Baolian Yi, Xinge Zhang, Enjun Zhang

Journal of Electrochemistry

The perchlorate was made up of a lead dioxide plate elcetrode and an oxygen cathode. By measuring the flow capacity of cell gas in the cell, and by means of CV, SEM, XRD, the performances of the lead dioxide plate electrodes are evaluated. The influence of changes in the concentrations of electroplating solutions (F, HNO3, Bi3+, Ni2+, Fe3+ and surface active agent) is investigated. The results show that the concentrations of Fe3+ in the solutions must be lower 0.01 g/L, and the concentrations of HNO3 in the solutions are about 20 …

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Study Of〔Co(2. 5 Nm) Pt(2. 5 Nm)〕N (N≥50) Multilayer By Electrocrystallization, Renhe Yin, Weiming Cao, Yanpin Guo, Huifen Ji Aug 1997

Study Of〔Co(2. 5 Nm) Pt(2. 5 Nm)〕N (N≥50) Multilayer By Electrocrystallization, Renhe Yin, Weiming Cao, Yanpin Guo, Huifen Ji

Journal of Electrochemistry

The electrocrystallization of Co(2.5 nm)/Pt(2.5 nm)n (n ≥50) multilayer has been carried out under potential control, based on observation of reflection electron microscopy (REM). Monatomic steps on Pt single crystal surfaces have been imaged using a conventional transmission electron microscope in the reflection made. The REM images have revealed three dimintional growth of Co electrocrystallization at high polarization of -1.15 V (vs.Hg/Hg2SO4). The structure of the specimen was examined by small or high angle X-ray diffration technique. The modulation period of a multilayered structure is 5.0 nm.

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Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅲ. Improvement Of Artificially Imposed Solid Electrolyte Film On Cell Performance, Shuhua Ma, Xiabin Jing, Fosong Wang Aug 1997

Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅲ. Improvement Of Artificially Imposed Solid Electrolyte Film On Cell Performance, Shuhua Ma, Xiabin Jing, Fosong Wang

Journal of Electrochemistry

The improving effect of solid electrolyte film artificially imposed on carbon electrode was investigated. The result showed that both the charge/discharge capacity and first charge/discharge efficiency, to a certain extent, were enhanced, and the result also suggested the effectiveness of the substitution of the artificially imposed solid electrolyte film for the inherent passivating film which was formed on the surface of the carbon electrode while inserted in the electrolyte during charging or discharging. The Scanning Electron Microscope result displayed the compact and well-defined morphology of the artificially imposed crystalline film.

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Studies On The Failure Modes Of Stationary Vrla Batteries, Yibo Tong, Xiangming Qiu Aug 1997

Studies On The Failure Modes Of Stationary Vrla Batteries, Yibo Tong, Xiangming Qiu

Journal of Electrochemistry

In order to improve the reliability and the quality of stationary valve-regulated lead-acid (VRLA) batteries, the failure modes of the stationary VRLA batteries which caused by the water loss and the thermal runaway are studied. The water loss may be solved by increasing the Oxygen-recombination efficiency, choosing the suitable grid material and the additives of megative paste, decreasing the corrosion of the positive plates. The thermal runaway may be solved by decreasing the inner ohmic resistance of VRLA batteries, improving the outside condition of batteries such as putting into the absorbing-heat material between the abtteries etc..

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The Electrochemical Behavior And Deposited Mechanism Of Zn-Ni Alloy Codeposition, Jixun Wu, Yongqin Liu, Huimin Meng Aug 1997

The Electrochemical Behavior And Deposited Mechanism Of Zn-Ni Alloy Codeposition, Jixun Wu, Yongqin Liu, Huimin Meng

Journal of Electrochemistry

The electrochemical behavior of Zn-Ni alloy codeposition and concomitant hydrogen evolution have been studied in the chloride ammonia solution through the d-c electroplating method. Under the condition of the applied cathodic current density of 2A/dm2 , the AC impedance spectra have been measured. An equivalent circuit has been presented for the impedance study on the alloy codeposition.

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A Fluid In Contact With A Semipermeable Surface: Second-Order Integral Equation Approach, Douglas Henderson, Pawel Bryk, Stefan Sokolowski Aug 1997

A Fluid In Contact With A Semipermeable Surface: Second-Order Integral Equation Approach, Douglas Henderson, Pawel Bryk, Stefan Sokolowski

Faculty Publications

An integral equation approach for a binary hard-sphere mixture interacting with a planar semipermeable wall (membrane) is formulated by using the second-order nonuniform or pair Ornstein–Zernike equation as well as the usual singlet Ornstein–Zernike equation. The results of the pair theory are compared with those obtained from the singlet theory and with computer simulation data. The pair approach is more accurate than the singlet theory.

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Emissions From Smoldering Combustion Of Biomass Measured By Open-Path Fourier Transform Infrared Spectroscopy, Robert J. Yokelson, Ronald A. Susott, Darold E. Ward, James J. Reardon, David W. T. Griffith Aug 1997

Emissions From Smoldering Combustion Of Biomass Measured By Open-Path Fourier Transform Infrared Spectroscopy, Robert J. Yokelson, Ronald A. Susott, Darold E. Ward, James J. Reardon, David W. T. Griffith

Chemistry and Biochemistry Faculty Publications

Biomass samples from a diverse range of ecosystems were burned in the Intermountain Fire Sciences Laboratory open combustion facility. Midinfrared spectra of the nascent emissions were acquired at several heights above the fires with a Fourier transform infrared spectrometer (FTIR) coupled to an open multipass cell. In this report, the results from smoldering combustion during 24 fires are presented including production of carbon dioxide, carbon monoxide, methane, ethene, ethyne, propene, formaldehyde, 2-hydroxyethanal, methanol, phenol, acetic acid, formic acid, ammonia, hydrogen cyanide, and carbonyl sulfide. These were the dominant products observed, and many have significant influence on atmospheric chemistry at the …

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Age-Dependent Increase In Ortho-Tyrosine And Methionine Sulfoxide In Human Skin Collagen Is Not Accelerated In Diabetes: Evidence Against A Generalized Increase In Oxidative Stress In Diabetes, Mary C. Wells-Knecht, Timothy J. Lyons, David R. Mccance, Suzanne R. Thorpe, John W. Baynes Aug 1997

Age-Dependent Increase In Ortho-Tyrosine And Methionine Sulfoxide In Human Skin Collagen Is Not Accelerated In Diabetes: Evidence Against A Generalized Increase In Oxidative Stress In Diabetes, Mary C. Wells-Knecht, Timothy J. Lyons, David R. Mccance, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The glycoxidation products Nepsilon-(carboxymethyl)lysine and pentosidine increase in skin collagen with age and at an accelerated rate in diabetes. Their age-adjusted concentrations in skin collagen are correlated with the severity of diabetic complications. To determine the relative roles of increased glycation and/or oxidation in the accelerated formation of glycoxidation products in diabetes, we measured levels of amino acid oxidation products, distinct from glycoxidative modifications of amino acids, as independent indicators of oxidative stress and damage to collagen in aging and diabetes. We show that ortho-tyrosine and methionine sulfoxide are formed in concert with Nepsilon-(carboxymethyl)lysine and pentosidine during glycoxidation of collagen …

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Predicting Electron Affinities With Density Functional Theory: Some Positive Results For Negative Ions, Gregory S. Tschumper, Henry F. Schaefer Aug 1997

Predicting Electron Affinities With Density Functional Theory: Some Positive Results For Negative Ions, Gregory S. Tschumper, Henry F. Schaefer

Chemistry Faculty Research & Creative Works

The atomic electron affinities of the eight first row (H,Li,...,F) atoms as well as the adiabatic electron affinities of 12 first row diatomic and 15 first row triatomic molecules were determined using six different densities functional or hybrid Hartree-Fock/density functional methods. The 35 species were selected for having relatively well-established experimental electron affinities. Harmonic zero-point vibrational energy corrected electron affinities are also reported for the diatomic and triatomic molecules. Equilibrium geometries and harmonic vibrational frequencies are given for the 27 molecules and their anions as determined with each density functional method. Discussion focuses on comparison of theoretical and experimental electron …

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Scanning Motions Of An Atomic Force Microscope Tip In Water, Kenichiro Koga, Xiao Cheng Zeng Aug 1997

Scanning Motions Of An Atomic Force Microscope Tip In Water, Kenichiro Koga, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Integral equation techniques are used to study scanning motions of a single-atom tip of the atomic force microscope (AFM) over a rigid, hydrophobic monolayer substrate in water. The calculated force curve is found to be oscillatory, in agreement with recent AFM experiments, which can lead to multiple scanning trajectories for the tip under a constant load. The unique trajectory along which the system is thermodynamically stable is revealed. This study shows that the tip may take a hopping motion over a defect-free substrate due to layering of water molecules between the tip and substrate.

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39th Rocky Mountain Conference On Analytical Chemistry Aug 1997

39th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Preliminary program and registration information for the 39th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 3-7, 1997.

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A Study Of The Volatile Matter Of Coal As A Function Of The Heating Rate, Enrique Santos Aug 1997

A Study Of The Volatile Matter Of Coal As A Function Of The Heating Rate, Enrique Santos

Masters Theses & Specialist Projects

A study of volatile matter yields as a function of the heating rate was conducted. A suite of 21 coal and coke samples varying in rank from anthracitic to lignitic and heating rates from 10°C/min to about 450°C/min were used in the study. Heating rates up to 60°C per minute, which are typically used in ASTM Test Method 5142 (instrumental Proximate Analysis), were achieved in a macro thermogravimetric analysis (TGA) system. Heating rates of 50-200°C/min were obtained in a micro TGA system. All measurements were made in a nitrogen atmosphere. The results of the study illustrate the dependance of the …

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Extraction Of Premafloxacin Radiolabeled With Carbon Fourteen From Loam Soil, Steven Gregory Staskiewicz Aug 1997

Extraction Of Premafloxacin Radiolabeled With Carbon Fourteen From Loam Soil, Steven Gregory Staskiewicz

Masters Theses

Premafloxacin is a fluoroquinolone antibiotic being developed by Pharmacia & Upjohn for veterinary indications. Since the parent drug and possibly metabolites will be applied to soil through the deposition of animal excreta, many regulatory agencies will require environmental assessment testing. In order to determine if 14C-premafloxacin would biodegrade in the soil, loam soil was extracted with solvents and C18 solid phase columns were used to isolate the compound after three weeks of incubation. In addition to extracting the soil, production of 14CO2 was monitored by trapping the degradation by-product in 2 N NaOH. Liquid scintillation counting of …

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Breakdown Of The Iron Passive Layer By Use Of The Scanning Electrochemical Microscope, David O. Wipf, John W. Still Aug 1997

Breakdown Of The Iron Passive Layer By Use Of The Scanning Electrochemical Microscope, David O. Wipf, John W. Still

Publications

The scanning electrochemical microscope (SECM) is used to generate localized corrosion at passivating iron surfaces by using the tip to generate Cl– ions. Use of the SECM allows the rapid establishment of a locally aggressive chemical environment at a pre-selected site on the iron surface. The susceptibility for passive-layer breakdown and corrosion initiation was examined as a function of the time between the start of the passive-layer growth and the formation of Cl- ions. The breakdown of the passive-layer was found to depend strongly on the passivation potential and the site of Cl- formation on the iron …

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Toward A Molecular Theory Of Vapor-Phase Nucleation. V. Self-Consistency In The Decoupled Dimer Limit, K.J. Oh, Xiao Cheng Zeng, H. Reiss Jul 1997

Toward A Molecular Theory Of Vapor-Phase Nucleation. V. Self-Consistency In The Decoupled Dimer Limit, K.J. Oh, Xiao Cheng Zeng, H. Reiss

Xiao Cheng Zeng Publications

The previous papers of this series introduced a molecular i / υ cluster theory of vapor phase nucleation. This theory differs from most conventional ones in that the cluster (due to fluctuation) is not only characterized by its number of particles i but also by a spherical volume υ. Thus the free energy of formation of the cluster is not merely a one-dimensional function of the number of particles i but a two-dimensional function of both i and v (i.e., it is a free energy surface). In the first stage of this development (Refs. 1–3) the theory is based on …

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Nondipole Resonant X-Ray-Raman Spectroscopy: Polarized Inelastic Scattering At The K Edge Of Cl2, J. D. Mills, J. A. Sheehy, T. A. Ferrett, S. H. Southworth, R. Mayer, Dennis W. Lindle, P. W. Langhoff Jul 1997

Nondipole Resonant X-Ray-Raman Spectroscopy: Polarized Inelastic Scattering At The K Edge Of Cl2, J. D. Mills, J. A. Sheehy, T. A. Ferrett, S. H. Southworth, R. Mayer, Dennis W. Lindle, P. W. Langhoff

Chemistry and Biochemistry Faculty Research

Experimental and theoretical studies are reported on the inelastic (Raman) scattering of wavelength-selected polarized x rays from the K edge of gas-phase chlorine molecules. The polarized emission spectra exhibit prominent nondipole features consequent of phase variations of the incident and emitted radiation over molecular dimensions, as predicted by the Kramers-Heisenberg scattering formalism. Issues pursuant to the detection of core-hole localization by resonant Raman scattering from homonuclear diatomic molecules are critically examined. [S0031-9007(97)03486-8]

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