ERSC 2P21 Lecture Notes - Lecture 8: Coordination Geometry, Linus Pauling, Coordination Number

• School: Brock University
• Department: Earth Sciences
• Course: ERSC 2P21
• Professor: Mariek Schmidt

Document Summary

In ionic and metallic solids, we can actually assume ions are spheres! Each c is bonded to 4 other c atoms, forming a structure consisting of corner sharing tetrahedral in a framework. = rc:ra: where rc is the radius of the cation and ra is the radius of the anion, rna+ = 1. 02 (for c. n. Two choices are available for positioning of the 3rd layer of spheres. Two choices for the third layer : above the a position. Closest packing of spheres two choices for position of layer 3: a or c. Layer 1 = a: layer 3 = a (ababab ) or layer 3 = c (abcabc ) cubic. Many native metals are formed by closest packing of spheres (ccp or hcp) examples: gold (ccp, silver (ccp, copper (ccp, this close packing of metal cations lends these native metals great density!