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Updated: Oct 25, 2025
Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
Double Double to Double Perovskite Transformations in Quaternary Manganese Oxides
Kunlang Ji1, Khalid N Alharbi1, Elena Solana-Madruga1,2
1Centre for Science at Extreme Conditions (CSEC) and School of Chemistry, University of Edinburgh, Mayfield Road, Edinburgh, EH9 3JZ, UK.
Abstract:
Control of cation ordering in ABX3 perovskites is important to structural, physical and chemical properties. Here we show that thermal transformations of AA'BB'O6 double double perovskites, where both A and B sites have 1:1 cation order, to (A0.5 A'0.5 )2 BB'O6 double perovskites with fully disordered A/A' cations can be achieved under pressure in CaMnMnWO6 and SmMnMnTaO6 , enabling both polymorphs of each material to be recovered. This leads to a dramatic switch of magnetic properties from ferrimagnetic order in double double perovskite CaMnMnWO6 to spin glass behaviour in the highly frustrated double perovskite polymorph. Comparison of double double and double perovskite polymorphs of other materials will enable effects of cation order and disorder on other properties such as ferroelectricity and conductivity to be explored.
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