Research on Crystal Chemistry Studies

This research program is presently concerned with light scattering from dispersed metallic spheres that have been coated with a passive layer to reduce cohesion and to prevent excessive material degradation. Various mechanisms for the cohesion of spheres are investigated and the conditions under which particular mechanisms become dominant are determined. Using the Lenard-Jones potential as a mathematically convenient model potential for the molecular attraction of spheres, the thickness of a molecular-solid coating required to saturate the molecular binding from strong metallic binding to relatively weak van der Waals binding is estimated. The theory lf light scattering from coated spheres is investigated. The qualitative relationship between actual metallic spheres and perfectly conducting spheres is explored along with the qualitative similarity of coated metallic sheres and perfectly conducting spheres. Quantitative effects of nondispersive, absorbing, and nonabsorbing coatings of various thicknesses are determined. In the final part of this section, Lorentzian absorption lines of various linewidths are used as models for absorption and dispersion in actual coatings. A listing of the computer program for calculating the scattering from coated spheres and descriptions of the subroutines are given in the appendices.