X-ray diffraction (XRD)

The XRD Rigaku MiniFlex 600 XRD Diffractometer was powered and from the panel, the voltage and current were set at 30kV and 15 mA. The temperature was set at 21-23oC. The computer system was switched on and the software of XRD, TUMI was double clicked to run. The settings dialogue was clicked and all the required setting of power and temperature were checked to correspond to that of the XRD. The analyzed material was finely ground, homogenized, and average bulk composition is determined. The powdered sample was then prepared using the sample preparation block and compressed in the flat sample holder to create a flat, smooth surface that was later mounted on the sample stage in the xrd cabinet.

Sample was poured into the sample holder and then placed in the sample chamber column. Then the door was shut and confirmed from the computer. The sample was analysed using the reflection-transmission spinner stage using the Theta-Theta settings. Two-Theta starting position was 4 degrees and ends at 75 degrees with a two-theta step of 0.026261 at 8.67 seconds per step. Tube current was 40mA and the tension was 45VA. A Programmable Divergent Slit was used with a 5mm Width Mask and the Gonio Scan was used.

The intensity of diffracted X-rays is continuously recorded as the sample and detector rotate through their respective angles. A peak in intensity occurs when the mineral contains lattice planes with d-spacings appropriate to diffract X-rays at that value of θ. Although each peak consists of two separate reflections (Kα1 and Kα2), at small values of 2θ the peak locations overlap with Kα2 appearing as a hump on the side of Kα1. Greater separation occurs at higher values of θ. Typically these combined peaks are treated as one. The 2λposition of the diffraction peak is typically measured as the center of the peak at 80% peak height. Results are commonly presented as peak positions at 2θ and X-ray counts (intensity) in the form of a table or an x-y plot (shown above). Intensity (I) is either reported as peak height intensity, that intensity above background, or as integrated intensity, the area under the peak. The relative intensity is recorded as the ratio of the peak intensity to that of the most intense peak

(relative intensity = I/I1 x 100 ). The result obtained was then match with different library, such as the NIST and PubChem in order to get the chemical structure, name, and other physicochemical properties