Determination of coordination number and packing fraction of metal chloride models

Abstract

This project is meant to describe the structures of metal chlorides by using models where the metal and chloride ions are arranged alternately at the lattice points of the cubic lattice. Metal chlorides have different crystal structures due to arrangement of atoms inside them. The atomic arrangement of the crystal is made by repeatedly placing a unit cell consisting of a small number of atoms according to the rules for assembling the crystal lattice. The major objective was to determine the coordination number and packing fraction of any three metal chlorides and model the structure of each metal chloride and determine the extent of packing. It was noted that sodium chloride structure is densely packed with 74 %of its structure filled with atoms followed by Iron II chloride which had 68 %of its lattice filled with atoms and then ceasium chloride being less dense with 52 %of its lattice filled with atoms. This means that sodium chloride has a stable chloride structure than the other two metal chlorides. But an improvement was required to be done to increase on the efficiency of packing of atoms to improve on the stability of the metal chlorides.