How Is Fepo4 Formed From A Temperature Range Of 294K To 1073?

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The structural evolution of FePO4 studied from a temperature range of 294K to 1073K by neutron powder diffraction. It is unique from α-quartz isotopes. It is different because it’s a cation is a transition metal. The structure dimensions and atomic coordinates in the α phase tend to increase by great amounts as the high-temperature β-phase rises and exhibit first order transition at 980K. The atomic structure dimensions of the α-phase FePO4 increased in a non-uniform pattern with respect to temperature. A thermal expansion coefficient α (K-1)= 2.924 x 10-5 + 2.920 x 10-10 ( T-300)2 is used to get its volume results. Angular variations caused by the changes in the 2 symmetrically-independent Fe-O-P bridging angles as well as
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The resultant average tilt angle δ is being used as the individual average tilt angles. The behaviour of FePO4 does not follow the behaviour of other α-quartz homeotypes. The δ angle begins to decrease more rapidly than …show more content…
The structural evolution of this quartz type iron phosphate, FePO4 was observed using neutron powder diffraction from temperature varying from 294K-1073K. It also have a α-β phase transition at high temperature (980K).The refined structural parameters of the low temperature α phase tend towards the obtained values for high temperature β quartz type FePO4. The irregularities increase with the increasing temperature due to the excited low energy, high amplitude vibration in αquartz and resulted by the non-physical behaviours. The effect of this disorder is accommodated total neutron scattering measurement. In a tetrahedral distortion there is a change in both the angle and the length of the bonds which are present during the tetrahedral tilting. Only a change in the angle is resulted but no significance change in bon length. The increase in bridging angles between Fe—O—P and the tetrahedral angles greatly decrease as the α-β transition approach at high temperature at 980K. The tetrahedral tilt angle δ and the intertetrahedral bridging angle θ can be related to the degree of distortion with respect to β-quartz structure type. The α-β transition is not observed for most material under the condition that δ value is greater than 22 degrees and θ value less than 136 degrees. However, the structural parameters of FePO4

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