Garnet typically has the chemical formula: (Fe2+, Mg2+, Ca 2+,Mn2+)3 Al3+2Si4+3O12
The formula can be broken up into structural sites (spaces wherecations of a certain size range can occupy) X3Y2Z3O12 where theX-site is coordinated with 8 oxygen anions, the Y-site iscoordinated with 6 oxygen anions, and the Z-site is coordinatedwith 4 oxygen anions. Using the table of ionic radii, calculate thepredicted coordination number (CN) relative to O2- for each cationin the garnet formula. How do the calculated CNs compare to thosefor real garnet? Explain why they are the same or different.
