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Photoelectron spectrometry

There has been a great deal of interest since the mid 1970s in photoelectron spectrometry and the ionization potentials of various A,B-diheteropentalenes have been summarized 84CHEC-I(4)1037 . The photoelectron spectrum of thieno[3,2-6]thiophene (12) was measured in the solid state as well as in the gas phase and has been investigated in comparison with linearly polycondensed poly thiophenes, (66) and (67) 92JCS(P2)765 . [Pg.13]

Diradical species 35a and 35b, in which two imino nitroxide 35a or nitronyl nitroxide 35b radical centers are attached to thieno[2,3-. ]thiophene, were prepared and their intramolecular exchange interactions were investigated in frozen solutions by means of electron spin resonance (ESR) spectroscopy and magnetic susceptibility measurements at cryogenic temperature 1996T6893 . [Pg.9]


Dynamic SIMS is used to measure elemental impurities in a wide variety of materials, but is almost new used to provide chemical bonding and molecular information because of the destructive nature of the technique. Molecular identihcation or measurement of the chemical bonds present in the sample is better performed using analytical techniques, such as X-Ray Photoelectron Spectrometry (XPS), Infrared (IR) Spectroscopy, or Static SIMS. [Pg.533]

One other technique has become central in surface research this is X-ray photoelectron spectrometry, earlier known as ESCA, electron spectroscopy for chemical analysis . Photoelectrons are emitted from a surface irradiated by X-rays. The precautions which have to be taken to ensure accurate quantitative analysis by this much-used technique are set out by Seah (1980). [Pg.408]

Charge distributions and bonding in compounds of Cd and Hg in the solid and gaseous states can be studied by the well-established X-ray photoelectron spectrometry (XPS) and ultraviolet photoelectron spectrometry (UPS), respectively. With XPS, inner-shell electrons are removed which are indirectly influenced by the bonding, i.e., distribution of the valence electrons. UPS sees this electron distribution directly, since it measures the residual kinetic energies of electrons removed from the valence shells of the atoms, or, better, from the outer occupied orbitals of the molecules. The most detailed information accessible by UPS is obtained on gases, and it is thus applied here to volatile compounds, i.e., to the halides mainly of Hg and to organometallic compounds. [Pg.1256]

ARUPS Angle Resolved Ultraviolet Photoelectron Spectrometry... [Pg.22]

Watson RE, Perlman ML (1975) X-ray photoelectron spectroscopy, application to metals and alloys. In Dunitz JD et al. (eds) Photoelectron spectrometry. Structure and bonding, vol 24. Springer, Berlin... [Pg.140]

As mentioned already, many surface-analysis techniques are available nowadays. In the opinion of some specialists in this field [36, 37], four of these are greater in importance X-ray photoelectron spectrometry (ESCA), Auger electron spectrometry (AES), secondary-ion mass spectrometry (SIMS), and low-energy ion scattering spectrometry (ISS). [Pg.450]

X-Ray Photoelectron Spectrometry. X-ray photoelectron spectrometry (XPS) was applied to analyses of the surface composition of polymer-stabilized metal nanoparticles, which was mentioned in the previous section. This is true in the case of bimetallic nanoparticles as well. In addition, the XPS data can support the structural analyses proposed by EXAFS, which often have considerably wide errors. Quantitative XPS data analyses can be carried out by using an intensity factor of each element. Since the photoelectron emitted by x-ray irradiation is measured in XPS, elements located near the surface can preferentially be detected. The quantitative analysis data of PVP-stabilized bimetallic nanoparticles at a 1/1 (mol/mol) ratio are collected in Table 9.1.1. For example, the composition of Pd and Pt near the surface of PVP-stabilized Pd/Pt bimetallic nanoparticles is calculated to be Pd/Pt = 2.06/1 (mol/ mol) by XPS as shown in Table 9.1.1, while the metal composition charged for the preparation is 1/1. Thus, Pd is preferentially detected, suggesting the Pd-shell structure. This result supports the Pt-core/Pd-shell structure. The similar consideration results in the Au-core/Pd-shell and Au-core/Pt-shell structure for PVP-stabilized Au/Pd and Au/Pt bimetallic nanoparticles, respectively (53). [Pg.447]

Ion scattering spectrometry (ISS) Secondary ion mass spectrometry (SIMS) Auger electron spectrometry (AES) X-ray photoelectron spectrometry (XPS)... [Pg.63]

In certain applications (e.g., X-ray photoelectron spectrometry) an electron beam must be analyzed by its kinetic energy using a 180° hemispherical energy analyzer consisting of two concentric hemispheres coupled to a wide-area charge-coupled detector (see Fig. 10.29). [Pg.642]

Engelking, PC. Lineberger, W. C. Laser photoelectron spectrometry of NH- electron affinity and intercombination energy difference in NH, J. Chem. Phys. 1976,65, 4323-4324. [Pg.365]


See other pages where Photoelectron spectrometry is mentioned: [Pg.235]    [Pg.1253]    [Pg.1256]    [Pg.26]    [Pg.28]    [Pg.28]    [Pg.34]    [Pg.9]    [Pg.34]    [Pg.34]    [Pg.62]    [Pg.64]    [Pg.609]    [Pg.221]    [Pg.109]    [Pg.32]    [Pg.113]    [Pg.482]    [Pg.32]    [Pg.113]    [Pg.13]    [Pg.810]    [Pg.362]    [Pg.113]    [Pg.2]    [Pg.2]    [Pg.341]    [Pg.173]    [Pg.241]    [Pg.85]    [Pg.93]    [Pg.240]   
See also in sourсe #XX -- [ Pg.478 ]

See also in sourсe #XX -- [ Pg.213 , Pg.355 ]




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Ultraviolet photoelectron spectrometry

X-ray Photoelectron Spectrometry (XPS)

X-ray photoelectron spectrometry

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