FePO4 is made up of iron, phosphorus, and oxygen. What differentiate FePO4 from the other α-quartz isotype is that iron is a transition metal. With its transition metal properties, it has a varied temperature range of 294K to 1073K. At different temperature and pressure, it occupies a different kind of shapes and sizes. At a low temperature, the structure will be of a α-quartz, which is tetrahedral in size. Whereas at a high pressure, the structure will be of a β-quartz, and it will have a denser octahedral structure.
Crystal structure of quartz
Due to its cell parameters and atomic coordinates in its different phrases, it tends to exhibit a first order temperature transition at 980K. For FePO4, an increase in temperature will lead to a non-continuous expansion of its cell parameters. The reasons for its non-continuous expansion are a few: the first being the angular variations affecting the symmetrically independent intertetrahedral, and the second being its volume is dependent on its structure angle. To determine…show more content… In the event that the δ is greater than 22 and θ value is of a smaller number than 136, then the typical α-β that is expected to occur will not occur for most material. Defying from the norm, the structural parameters of FePO4 does differ, when the amount is δ=21.5o and θ= 137.8o. When placed in a tall temperature of four hours, the outcome will be that the length and angle of FeO4 of FePO4 will experience a change. In further explanation, it will be that the Fe-O2 length actually decreases. With the length becoming shorter, the angle thus shrinks in size too. This affects the compound and causes it to have a change of unit cell size and volume. In comparison to its counterpart, the P-O4 bond will have an increase in temperature when there is compression, and this in turn will cause the bond angle to