Hello everyone
I recently did the XRD phi scans on the (110) oriented SrTiO3 (STO) single crystal substrate that has a cubic crystal structure. The phi scans were measured along the (001) or (111) zones. But the results only have two peaks, as shown below.
Previously, I did the similar phi scans on the (100) oriented STO single crystals. It has four peaks, which is reasonable for the four-folder symmetry of the cubic system.
Also, for the (111) oriented STO, the phi scans always show three peaks with 120 deg. apart.
Could anyone explain why the phi scan results are different in these cases? Especially, why the (110) STO only has two peaks? Thank you very much.