Local insight into electric ordering

Local and average structure of dimethylammonium manganese formate

Hybrid perovskite analogues – materials that combine small organic ions with metals to create a framework structure – have important applications in fields ranging from solar power generation to computing and data storage. In a recent experiment, CCMMP PhD student Helen Duncan, together with her supervisors Dr Anthony Phillips and Prof. Martin Dove, used neutron scattering data from the GEM instrument at ISIS Neutron and Muon Source to investigate one such material, dimethylammonium manganese(II) formate. Analysing the data using the reverse Monte Carlo method revealed the local structure of the material: exactly the detail that is missed by conventional crystallographic techniques that yield the spatial average structure. Their work, recently published in a special edition of Dalton Transactions on "Flexibility and Disorder in Metal-Organic Frameworks", revealed that the electrical ordering arising from the motion of the dimethylammonium ions in the pores of the framework is assisted by subtle deformations of the framework itself.