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I am an inorganic chemist and I am looking for some guidance on where to find a mathematical/physical description of phenomena which I have been observing in a solid-state transformation. I am working with a crystalline oxide (MoO3) which I expose to elevated temperatures (750C) in a strongly reducing atmosphere (H2/CH4) to effect the transformation:

MoO3 --> MoO2 --> Mo2C

The materials have successively increasing density (cf. 4g/cm3 - 6g/cm3 - 9g/cm3) and for reasons I wont go into, the overall morphology and (aggregate) particle sizes are retained through the reaction albeit in highly fragmented forms. This results in a large increase in surface area with each transformation. The final surface area appears to be unrelated to the initial surface area of the starting material which makes me wonder what basic principles lie behind the fracturing of the initial crystal form and formation of the final contracted particles.

Please let me know if the problem is not clear enough and I will try to explain more fully. Thanks for reading this far!

cheers

Tom

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# Solid-state transformations in crystalline material

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