Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Electronic spectroscopy overview

This review is intended to serve two purposes. First, it attempts to provide a comprehensive overview of the current state of knowledge regarding the electronic spectroscopy and the primary photochemistry of a number of important hydride molecules. Second, it gives us an opportunity to advertise the enormous potential of the H(D)-atom photofragment translational spectroscopy experiment. We believe it is fair to claim that the technique... [Pg.278]

Magnetic resonance plays a role in biophysical spectroscopy of ever increasing importance and diversity. The topic is conveniently and conventionally divided into three domains (1) nuclear magnetic resonance (NMR) spectroscopy, (2) Mdssbauer spectroscopy, and (3) electron paramagnetic resonance (EPR) spectroscopy. All three of these methods depend on the presence of a magnetic moment, either that of a nucleus or of an unpaired electron. This overview is confined to the topic of EPR as the biological applications of NMR are so extensive that they receive dedicated reviews (e.g.. Volume 239 in this series) and the biochemical applications of Mdssbauer spectroscopy have been reviewed elsewhere in this series. ... [Pg.529]

Spectrometry Overview. Mercury. Microscopy Techniques Scanning Electron Microscopy X-Ray Microscopy. Particle Size Analysis. Polychlorinated Biphenyls. Polycyclic Aromatic Hydrocarbons Environmental Aj li-cations. Radiochemical Methods Overview. Sample Handling Sample Preservation. Sampling Theory. Surface Analysis Auger Electron Spectroscopy. Tin. X-Ray Absorption and Diffraction Overview. X-Ray Fluorescence and Emission Energy Dispersive X-Ray Ruores-cence Particle-Induced X-Ray Emission. [Pg.1999]

See also Chemiluminescence Overview. Chromatography Principles. Clinical Analysis Overview. Electron Spin Resonance Spectroscopy Biological Applications. Fluorescence Overview. Ion-Selective Electrodes Overview. Mass Spectrometry Overview. Microscopy Overview. Nuclear Magnetic Resonance Spectroscopy Overview. Ozone. Radiochemical Methods Overview. Sensors Overview. Spectrophotometry Overview. [Pg.3226]

See also Activation Anaiysis Neutron Activation Charged-Particle Activation Photon Activation. Atomic Emission Spectrometry Inductively Coupled Plasma. Atomic Mass Spectrometry Inductively Coupled Plasma. Mass Spectrometry Overview. Surface Analysis Particle-Induced X-Ray Emission Auger Electron Spectroscopy Ion Scattering Nuclear Reaction Analysis and Elastic Recoil Detection. X-Ray Fluorescence and Emission Wavelength Dispersive X-Ray Fluorescence Energy Dispersive X-Ray Fluorescence. [Pg.4568]

See also Surface Analysis Auger Electron Spectroscopy Ion Scattering Overview X-Ray Photoelectron Spectroscopy. [Pg.4633]

See also-. Asbestos. Carbohydrates Dietary Fiber Measured as Nonstarch Poiysaccharides in Riant Foods. Electrophoresis Polyacryiamide Geis. Forensic Sciences DNA Profiling Fibers. Fourier Transform Techniques. Functional Group Analysis. Infrared Spectroscopy Overview. Liquid Chromatography Size-Exclusion. Microscopy Techniques Light Microscopy Scanning Electron Microscopy. Proteins Overview. Textiles Synthetic. X-Ray Absorption and Diffraction Overview. [Pg.4740]

See also Infrared Spectroscopy Overview Sample Presentation Industrial Applications. Liquid Chromatography Size-Exclusion. Microscopy Overview Microscopy Techniques Light Microscopy Scanning Electron Microscopy. Nuclear Magnetic Resonance Spectroscopy Overview. Textiles Natural. [Pg.4749]

It is also common for pol3rmeric compoimds to form surface regions with compositions different from the bulk material, by selective diffusion of components. This process is termed blooming when the surface component is solid, and bleeding if it is liquid. Sulfur and fatty acid blooms can inhibit adhesion in rubber laminates (3). Laser desorption mass spectroscopy has been employed to identify surface species on vulcanized rubber (4). X-ray scattering methods for the study of polymer surfaces and interfaces have been reviewed (5). Other surface analysis techniques commonly used with polymers include attenuated total reflectance (6-8), electron microprobe (9), Auger electron spectroscopy (10), x-ray photoelectron spectroscopy (11), and scanning probe microscopic methods (12). Overviews on polymer surface analysis have been published (13,14). [Pg.312]

The hydrogen content Ch greatly influences structure and consequently electronic and optoelectronic properties. An accurate measurement of Ch can be made with several ion-beam-based methods see e.g. Arnold Bik et al. [54]. A much easier accessible method is Fourier-transform infrared transmittance (FTIR) spectroscopy. The absorption of IR radiation is different for different silicon-hydrogen bonding configurations. The observed absorption peaks have been indentified [55-57] (for an overview, see Luft and Tsuo [6]). The hydrogen content can be determined from the absorption peak at 630 cm , which includes... [Pg.5]

In this chapter, we first present a brief overview of the experimental techniques that we and others have used to study torsional motion in S, and D0 (Section II). These are resonant two-photon ionization (R2PI) for S,-S0 spectroscopy and pulsed-field ionization (commonly known as ZEKE-PFI) for D0-S, spectroscopy. In Section HI, we summarize what is known about sixfold methyl rotor barriers in S0, S, and D0, including a brief description of how the absolute conformational preference can be inferred from spectral intensities. Section IV describes the threefold example of o-cholorotoluene in some detail and summarizes what is known about threefold barriers more generally. The sequence of molecules o-fluorotoluene, o-chlorotoluene, and 2-fluoro-6-chlorotoluene shows the effects of ort/io-fluoro and ortho-chloro substituents on the rotor potential. These are approximately additive in S0, S, and D0. Finally, in Section V, we present our ideas about the underlying causes of these diverse barrier heights and conformational preferences, based on analysis of the optimized geometries and electronic wavefunctions from ab initio calculations. [Pg.159]

The historical development and elementary operating principles of lasers are briefly summarized. An overview of the characteristics and capabilities of various lasers is provided. Selected applications of lasers to spectroscopic and dynamical problems in chemistry, as well as the role of lasers as effectors of chemical reactivity, are discussed. Studies from these laboratories concerning time-resolved resonance Raman spectroscopy of electronically excited states of metal polypyridine complexes are presented, exemplifying applications of modern laser techniques to problems in inorganic chemistry. [Pg.454]

This book deals only with the chemistry of the mineral-water interface, and so at first glance, the book might appear to have a relatively narrow focus. However, the range of chemical and physical processes considered is actually quite broad, and the general and comprehensive nature of the topics makes this volume unique. The technical papers are organized into physical properties of the mineral-water interface adsorption ion exchange surface spectroscopy dissolution, precipitation, and solid solution formation and transformation reactions at the mineral-water interface. The introductory chapter presents an overview of recent research advances in each of these six areas and discusses important features of each technical paper. Several papers address the complex ways in which some processes are interrelated, for example, the effect of adsorption reactions on the catalysis of electron transfer reactions by mineral surfaces. [Pg.1]

Characterization is the foundahon for the development and commercialization of new zeolites and zeolite-containing catalysts and adsorbents. Chapter 4 provides an overview of the most commonly employed characterization techniques and emphasizes the uhlity and limitations of each of these methods. An example is provided as to how a multi-technique characterization approach is necessary in order to determine the structure of a newly invented zeolite. Techniques covered in this chapter include X-ray powder diffraction, electron microscopy, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and physical/ chemical methods. [Pg.626]

In the following, we will discuss a number of different adsorption systems that have been studied in particular using X-ray emission spectroscopy and valence band photoelectron spectroscopy coupled with DFT calculations. The systems are presented with a goal to obtain an overview of different interactions of adsorbates on surfaces. The main focus will be on bonding to transition metal surfaces, which is of relevance in many different applications in catalysis and electrochemistry. We have classified the interactions into five different groups with decreasing adsorption bond strength (1) radical chemisorption with a broken electron pair that is directly accessible for bond formation (2) interactions with unsaturated it electrons in diatomic molecules (3) interactions with unsaturated it electrons in hydrocarbons ... [Pg.68]


See other pages where Electronic spectroscopy overview is mentioned: [Pg.76]    [Pg.34]    [Pg.50]    [Pg.148]    [Pg.248]    [Pg.760]    [Pg.4]    [Pg.18]    [Pg.193]    [Pg.320]    [Pg.4]    [Pg.3032]    [Pg.267]    [Pg.153]    [Pg.54]    [Pg.158]    [Pg.104]    [Pg.1]    [Pg.345]    [Pg.268]    [Pg.408]    [Pg.72]    [Pg.529]    [Pg.25]   
See also in sourсe #XX -- [ Pg.532 , Pg.569 ]




SEARCH



Electrons overview

Overview electronic

Spectroscopy overview

© 2024 chempedia.info