Two dimensional x-ray diffraction (2D-XRD) studies on Olivine of U.S.A.

The olivine (mg,fe) 2sio4 of usa has been studied with two dimensional x-ray diffracto meter (d8 discover with gadds). the two distinct phases of orthorhombic structure,one with mg8 [fe2 sio4] and the other with mg2 sio4 is observed. we also observed phase transitions due to presence of iron and silicon preferably the structural change of mg8[fe2 sio4] from orthorhombic to spinnel like (spinnel chord) structure. magnesium ions in mg8[fe 2 sio4] shuffle,arrange at the five vertices of a pentagon and the remaining three at the central but with displaced position from the plane of the pentagon,thus resulting into a three dimensional spinnel chord like structure. we evidenced the same from diverse orientations of phase peaks and indeed from kossel lines.