三方相和四方相在XRD上的区别

The zoom-in patterns of (1 1 1) and (2 0 0) peaks in Fig. Samples 1-3 all exhibit rhombohedral phase because there is a split in the( 1 1 1 ) peak but no observable split in (2 0 0) peak; sample 4 exhibits MPB structure because no observable split exists in both ( 1 1 1) and (2 0 0) peaks but the (2 0 0) peak is broaden ; samples 5 and 6 both exhibit typical tetragonal phase as the ( 1 1 1) peak does not split but the (2 0 0) peak

does.