Electron spectroscopy for chemical analysis, ESC

Tables 1.3-1.5 show the result of analyses of several bonds between a substrate and a polyvinyl fluoride him using an acrylic adhesive. All surfaces were analyzed by electron spectroscopy for chemical analysis (ESC A). ESC A yields chemical analysis of organic surfaces in atomic percentage, with the exclusion of hydrogen, which is undetectable by this technique. To determine the type of bond failure, ESCA results for the failed surfaces are compared with those of the adhesive and the polyvinyl fluoride him.

Photoelectron spectroscopy investigates the intensity and energy of electrons which are removed from the valence orbital (low-energy photoelectron spectroscopy) or inner orbitals (high-energy photoelectron spectroscopy, also known as Electron Spectroscopy for Chemical Analysis, ESC A), by photons. 

Electron spectroscopy encompasses two main techniques. X-ray photoelectron spectroscopy (XPS also known as electron spectroscopy for chemical analysis ESC) and Auger electron spectroscopy (AES). Both techniques identify and quantify elements present and can indicate the chemical state or functionality of elements at the surface. For best results, AES relies upon the sample being electrically conducting and consequently it is very rarely used in polymer analysis [1]. Hence it is not discussed further here. 

Depending on the energy of the source, different electron energy levels can be studied. When X-ray photons are used, the electron core levels are excited and the technique is called XPS or ESC A (Electron Spectroscopy for Chemical Analysis). 

ADE = adiabatic detachment energies ESC A = electron spectroscopy for chemical analysis HOMO = highest occupied molecular orbitals MAES = metastable atom electron spectroscopy MIES = metastable ionization electron spectroscopy OAT = oxygen atom transfer PES = photoelectron spectra PEI = pulsed field ionization PIES = Penning ionization electron spectroscopy QM = quantum-mechanical REMPI = resonantly enhanced multiphoton ionization SC = semiclassical VDE = vertical detachment energies XPS = x-ray photoelectron spectroscopy ZEKE = zero electron kinetic energy Cp = cyclopentadienyl, Ph = phenyl, CeHs Tp =... 

X-ray photoeleclron spectroscopy is currently the most widely used surface analytical technique, and is therefore described here in more detail than any of the other techniques. At its inception by SiEGBAHN and coworkers [10] it was called ESC A (electron spectroscopy for chemical analysis), but the name ESCA is now considered too general, since many surface electron spectroscopies exist, and the name given to each one must be precise. Nevertheless, the name ESCA is still used in many places, particularly in industrial laboratories and their publications. Briefly, the reasons for the popularity of XPS are the exceptional combination of compositional and chemical information that it provides, its ease of operation, and the ready availability of commercial equipment. 

During a considerable long period, the gaseous chemisorption method is the sole one to probe the surface species of solid catalysts. Some of the modern techniques for surface measuring are Measurements of effusion works, Auger electron spectroscopy (AES), Electron spectroscopy of chemical analysis (ESC A), X-ray photoelectron spectroscopy (XPS), Electron probe microanalysis (EPMA), Ion probe microanalysis (IPM), Ion scattering spectroscopy (ISS), Second ion mass spectroscopy (SIMS), Low energy electron diffraction (LEED), Vibration spectrum and Mossbauer spectroscopy etc. All these techniques provide favorable conditions for the surface research indepth. 

---