Inelastic sensitivity

Xps is a surface sensitive technique as opposed to a bulk technique because electrons caimot travel very far in soHds without undergoing energy loss. Thus, even though the incident x-rays penetrate the sample up to relatively large depths, the depth from which the electron information is obtained is limited by the "escape depth" of the photoemitted electrons. This surface sensitivity of xps is quantitatively defined by the inelastic mean free path parameter which is given the symbol X. This parameter is defined to be the distance an electron travels before engaging in an interaction in which it experiences an energy loss. 

Surface sensitivity in LEED is provided by the limited mean free path for inelastic scattering of slow electrons. This mean fi-ee path is the distance traveled by an electron in the solid before it collides inelastically, loses energy, and thus becomes... 

Surface composition analysis by LEIS is based on the use of noble gas ions as projectiles, making use of the superb surface sensitivity of LEIS under these conditions. A consequence of this surface sensitivity is that the LEIS energy spectrum consists of lines, one per element, if the masses differ sufficiently. The lines are narrow, because inelastic energy losses play a minor role here. Thus, the information on the atomic species present is deduced from the energy of the back-scattered ions, which can be converted to the mass of the scattering center. (Eig. 3.55 [3.141]). In Eig. 3.55 it is shown that the mass range, where LEIS is sensitive, depends on the projectile mass. 

Inelastic deformation can cause product failure arising out of a massive realignment of the plastic s molecular structure. A product undergoing inelastic deformation does not return to its original state when its load is removed. It should be remembered that there are plastics that are sensitive to this situation and others that are not. 

Although most of the results described in this review are aimed towards an understanding of the electronic structure of the bulk solid, the most widespread applications of XPS exploit its surface sensitivity, as a result of the numerous interactions that an ejected photoelectron undergoes as it travels through the surface layers [2]. The photoelectron collides with other electrons, either elastically so that its trajectory changes, or inelastically so that its KE decreases (by 10-40 eV per collision) [2,19,20]. The distance travelled between inelastic collisions is called the... 

Supplementary to other vibrational spectroscopies, inelastic neutron scattering (INS) spectroscopy is a very useful technique for studying organic molecules as it is extremely sensitive to the vibrations of hydrogen atoms. INS spectroscopy has been used to analyze the molecular dynamics of the energetic compound ANTA 5 <2005CPL(403)329>. 

Theoretical work on inhomogeneous molecular distributions is as yet incomplete, but McNulty et al 6) have made some calculations on adsorbed molecules on the surface of particles. Their conclusion was that the angular distributions have structure and that the inelastic scattering intensity in the forward and backward directions is particularly sensitive to particle size. 

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