{HEAD ~ The reactants} can be heated between about 650° C. and 670° C. to produce {TAIL ~ type II clathrates} Na24Si136 and K24Si136 
{ HEAD ~ The reactants } can be heated between about 650 ° C. and 670 ° C. to produce { TAIL ~ type II clathrates } Na24Si136 and K24Si136
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH