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We discuss the excitation of forbidden vibrational transitions accompanying photoionization of linear triatomic molecules. Excitation of a single quantum of the antisymmetric stretching vibration is observed for molecules with inversion symmetry, as is the bending mode. Photoelectron spectra of the [N.sub.2][O.sup.+]([A.sup.2][PI]), C[O.sub.2.sup.+]([C.sup.2][[SIGMA].sup.+.sub.g]). and C[S.sub.2]+([B.sup.2][[SIGMA].sup.+.sub.u]) states obtained over a range of ionization energies exhibit contrasting behavior for the relative intensities of the forbidden vibrations. These energy-dependent vibrational branching ratios are shown to result from an intrachannel vibronic coupling mechanism. Moreover, this intrachannel coupling can be further divided into two cases, one in which the photoionization cross section is sensitive to geometry changes, and a second case in which it is nol. These different cases can be distinguished by comparing the experimental and theoretical results for ali three molecules. Key words: photoelectron spectroscopy, vibronic coupling, photoionization.

The physical-chemical analyses of the turbidity relaxations of small unilamellar lipid vesicles of different sizes are studied. It is shown that smaller vesicles can be electro-elongated easily due to the smaller bending rigidity and larger pore fraction.

It is reported that there is extensive use of diagrammatic techniques in the presentation of the kinetic theory of fluctuations in equilibrium classical fluids. The correlation functions and closely related response functions are graphically expressed and the cluster properties of the various renormalized interactions are analyzed.

A series of segmentally fluorinated alkanethiolate self-assembled monolayers (SAMs) were used to measure the attenuation lengths of photoelectrons in fluorocarbon films. A comparison study with the photoelectrons obtained using SAMs on gold is given.

The first principles and semiempirical methods are used in the study of chemisorption of toluene on the silicon surface. It is seen that the most stable configuration is dissociated and a detailed analysis is given.

A kinetic theory of fluctuations in equilibrium classical fluids is presented. A diagrammatic expression for the correlation function and the multipoint generalizations is derived.

Two like-charged polyelectrolyte gels create an extensive static friction when they slide over each other in water. It is proved that the like-charged gel interface cannot slip with each other until the shear stress(strain) overcomes a criticality.

Controlled grafting of well-defined polymer brushes on the hydrogen-terminated silicon substrates is investigated. Kinetic studies revealed that there is a linear increase in polymer film thickness with reaction time indicating that chain growth from the surface was a controlled process with a 'living' characteristic.

The sulphur K-edge X-ray absorption near-edge structure (XANES) spectra of self-assembled monolayers for a series of n-alkanethiols adsorbed on Ag(111) is studied. The effects of chain length and incidence angle on the XANES spectra are investigated.

The Cu(II)-poly(propylene imine) dendrimer complexes with a diaminobutane core (DAB-Am(sub n)-Cu(II)(sub x), n = 4 to 64, x = n/2) are investigated by using an extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) spectroscopies. The transmission electron microscopy (TEM) and EXAFS studies shows that the size of the Cu(0) nanoclusters decreases with increased generation of the dedrimer.

It is shown that entropies of desorption can be obtained from temperature programmed desorption (TPD) data. In addition, it is shown that the use of the readily available gas-phase thermodynamic data helps in the determination of the rate constants for surface reactions.

Presents experimental results for the alignment of photoions of nitrogen compounds over an extended energy range. Interpretation of the oscillator strength distributions for normally unresolved degenerate ionization channels; Sensitivity of the spectral dependence of the alignment to the molecular environment for photoejection.

Abstract: The molecular photoionization of N2 leading to the 3, 2 ion states and CO leading to the valence isoelectronic 5σ −1, 4σ −1 ion states has been studied using both theory and experiment. Vibrational branching ratios have been obtained in the 15–200eV photoelectron energy range. The analysis of the branching ratios for these processes shows a breakdown in the Franck–Condon approximation in the range of energies studied. Some of the deviations at lower energies are well documented as due to shape resonances, and in such cases we found good agreement between the present work and previous experimental and theoretical investigations of these photoionization channels. For both N2 and CO ionization, we also found that the partial wave cross sections have an interference pattern similar to a Young-type interference, which are related to molecular Cooper minima. Such features were also seen to induce non-Franck–Condon effects in the vibrational branching ratios at higher energies. The comparison of theory and experiment was facilitated by the introduction of an electronic factor (F) that is the logarithmic derivative of the cross section with respect to bond length and which could be directly related to the branching ratios. [Copyright &y& Elsevier]