Atomic in AES

The initial state for each of these processes contains a core hole on an atom. In AES, the vacancy is usually created either by a high-energy electron (5-10 keV) or by a photon. Commonly used photon sources Include Mg and Al, as noted above, Zr (2042 eV), Au (2123 eV) and Ag (2984 eV). The higher energy sources are useful for creating deeper lying core holes than are conveniently accessible with Mg or Al, but are not too useful for routine photoelectron studies because of the large linewidth (20). Once the hole is created, an electron... 

AES as well as XPS can be used for surface imaging, but the spatial resolution of AES is generally better. The reason is that the primary electron beam used for exciting the surface atoms in AES can be well focused on areas as small as a few nanometer. X-rays are more difficult to focus and additional techniques, not discussed here, are required to improve the spatial resolution in XPS, which for most instruments today is in the ten micrometer range. In order to acquire a chemical image an electronic guiding system scans the surface while the AES or XPS intensity of chosen peaks is measured and stored numerically. The chemical map of the surface thus produced... 

Molecular ion Weak, decreasing with increasing chain length and degree of branching. Both [M+H] and [M-H] can be stronger than M+ . Odd mass for odd number of N atoms in Ae molecule. 

The polymer we are concerned with is PB-1. In the past this polymer has been referred to as polybutylene, PB, PB-1, and polybutene, as well as its chemically correct name, PB-1. PB-1 is obtained by polymerization of butene-1 with a stereo-specific Z-N catalyst to create a linear, high molecular, isotactic, semicrystalline polymer. PB-1 combines the typical properties of conventional polyolefins with some characteristics of technical polymers. In chemical structure PB-ldiffers from polyethylene and polypropylene only by the number of carbon atoms in Ae monomer molecule, as in Fig. 2.22. 

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