Periodic surfaces scattering function

The intensity variation along the rod (i.e. as a function of or /) is solely contained in the structure factor it is thus related to the z-co-ordinates of the atoms within the unit-cell of this quasi-two dimensional crystal. In general, the rod modulation period gives the thickness of the distorted layer and the modulation amplitude is related to the magnitude of the normal atomic displacements. This is the case of a reconstructed surface, for which rods are found for fractional order values of h and k, i.e. outside scattering from the bulk. 

In Auger electron spectroscopy (AES) [31], the intensity of electrons scattered from a surface is measured as a function of their kinetic energy. Characteristic peaks in the energy distribution identify the elements present within the near surface region. AES is most often used in conjunction with LEED to characterise the composition and atomic structure of a surface or film. Knowing both the periodicity and relative composition of an overlayer is indispensable to deducing its atomic structure. 

In Figure 5.27, the scattered data shown in Figure 4.26 are now more or less aligned, strongly suggesting that the efficiency of the surface modification varies evenly as a function of P/K, or in other words, as a function of the contact area. Rather than the externally applied load, one must consider a combination of the load. Young s modulus and the shape of the tip, to predict the period of the structure. Since in this work the tip was always the same, with a radius of about 40 nm, the tip shape acts as a constant, so that there was no need to introduce the geometrical shape of the tip. 

---