Phase changes, on reflection

P-polarised light can be reduced to two components Px polarised parallel to the surface and Ps polarised perpendicular to the surface. The Px component also suffers a 180° phase change on reflection for all 9 and is thus blind to any surface species. However, the phase shift for the Pz component changes rapidly with 9. This results in the ratio of the standing wave/incident ray mean electric held strength, <( >/<( ,2 >, varying with 9 as shown in Figure 2.42. The above discussion has two important implications ... 

Figure 14.17 A light beam incident on a plate with a higher refractive index than the surrounding medium suffers a phase change on reflection so the incident peak is reflected as a trough...

In a more general case where medium 2 is absorbing, i.e., 2 is a complex quantity, the phase changes on reflection can be found from Eqs (3.12) and (3.20) as... 

In Section 3.1.1 we have discussed the phase changes on reflection. For the two-phase model of a crystal-vacuum interface which does not take into ac-coimt any transition layer, the complex bulk dielectric function of the crystal... 

Finally, the phase usually changes on reflection or refraction. The phase shift 3 can be determined from the amphtude coefficients using the following relationships ... 

The preparation of the reflecting silver layers for MBI deserves special attention, since it affects the optical properties of the mirrors. Another important issue is the optical phase change [ ] at the mica/silver interface, which is responsible for a wavelength-dependent shift of all FECOs. The phase change is a fimction of silver layer thickness, T, especially for T < 40 mn [54]. The roughness of the silver layers can also have an effect on the resolution of the distance measurement [59, 60]. 

This potential reflects itself in the titration curves of weak polyacids such as poly(acrylic acid) and poly(methacrylic acid) [32]. Apparent dissociation constants of such polyacids change with the dissociation degree of the polyacid because the work to remove a proton from the acid site into the bulk water phase depends on the surface potential of the polyelectrolyte. 

While s-polarized radiation approaches a phase change near 180° on reflection, the change in phase of the p-polarized light depends strongly on the angle of incidence [20]. Therefore, near the metal surface (in the order of the wavelength of IR) the s-polarized radiation is greatly diminished in intensity and the p-polarized is not [9]. This surface selection rule of metal surfaces results in an IR activity of adsorbed species only if Sfi/Sq 0 (/i = dipole moment, q = normal coordinate) for the vibrational mode perpendicular to the surface. 

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