Provide a procedure to prepare β-Li3TaO4 using Li2CO3 and Ta2O5 as precursors. Use the XRD data at right and the XRD caption below to help you decide the optimal synthetic conditions. Be as specific as you can (i.e. provide masses and temperatures), clearly explain the reason for each experimental step, and state any assumptions you made.
a) Heat Li2CO3 and Ta2O5 at 1100 C for 12 hours in a covered container, followed by a final heating at 1450 C for 6 hours in an open container.
b) Heat Li2CO3 and Ta2O5 at 1100 C for 12 hours in a covered container, followed by a final heating at 1450 C for 4 hours in a covered container.
c) Heat Li2CO3 and Ta2O5 at 1100 C for 12 hours in a covered container, followed by a final heating at 1460 C for 2 hours in a sealed container.
d) Heat Li2CO3 and Ta2O5 at 1100 C for 12 hours in a covered container, followed by a final heating at 1450 C for 6 hours in an open container, and then at 1460 C for 2 hours in a sealed container.