CALCULATION OF MADELUNG POTENTIALS FOR FAUJASITE-TYPE ZEOLITES .I.

Using the assumption of complete ionicity, Madelung potentials for the ions in ordered models of X and Y faujasites have been calculated for various cation sizes, valencies, and distributions. For monovalent zeolites the results of the calculations agree well with ionic distributions found from X-ray studies. For divalent zeolites divergences between the results of the calculations and ionic distributions derived from crystallographic studies are explained on the basis that the materials used for the X-ray diffraction work retained a small amount of water.