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2.3 Basic structure types

Pauling rules: understanding polyhedral structures

(1) A polyhedron of anions is formed about each) A polyhedron of anions is formed about each cationcation,,
(1
thee cationcation--anion distance is determined by the sum of ionic radiianion distance is determined by the sum of ionic radii
th
and the coordination number by the radius ratio:nd the coordination number by the radius ratio: r(cation)/r(anionr(cation)/r(anion))
a

Scenario for radius ratios:

worst case optimum low space filling