Fepo4 Temperature Synthesis

997 Words4 Pages
FePo4 is a unique isotope because a transition metal makes up the cation in the isotope where there is Fe2+ and Fe3+ ions that can shift states. A transition metal has different properties as compared to normal metals, especially in terms of how it is affected by temperature. At a temperature below 980K, the isotope has a structure that follows the α-quartz which is tetrahedral in shape. However, once it reaches above 980K, first order transitions occurs and the structure transforms into a β-quartz which is an octahedral structure. This unique temperature change, which is 980K, was found after putting the isotope into a neutron powder diffraction. As temperature increases, the size, which is the parameters and the volume of the quartz increased…show more content…
This change shows that, as temperature increases, the parameters of the cell increases, resulting ultimately in an increase in volume which follows a particular direction of the quartz. Therefore, the shape changes from a triangle unit cell to a hexagonal unit cell. The tilt angles, which is also known as the tetrahedral bond angle also decrease significantly as temperature increases. As a result, there is too much instability within the structure and thus the moment the temperature hits 980K, the quartz loses its form and changes shape due to bonds breaking. This leads to the parameters to be altered, therefore reaching the β-phase. In this phase, any increase in temperature would not bring about any change in the quartz as it is relatively more stable. In the β-phase, regardless of how much the temperature changes, the bond distance and angle wont change significantly. A larger bond distance results in the β phase having a much higher degree of dynamic disorder. The theα-β transition has high correlation with the tilt angle δ which is highly essential because FePO4 requires the use of the tilt angle where both the FeO4 and PO4 tetrahedral has individual average tilt angles that is highly dependent on where

    More about Fepo4 Temperature Synthesis

      Open Document