Preferential silicon site occupation in Y/sub 2/Fe/sub 14-x/Si/sub x/B

Neutron-diffraction and Mossbauer effect studies of Y/sub 2/Fe/sub 14-x/Si/sub x/B, where x is 0.28, 0.67, and 1.87, show that silicon preferentially occupies the 4c site in the R/sub 2/Fe/sub 14/B structure. If the breaking of short iron-iron bonds is the mechanism for the increase in the Curie temperature of R/sub 2/Fe/sub 14-x/Si/sub x/B, then the bonds most responsible for the increase are those between iron atoms on the 16k/sub 2/ and 4c sites.<
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