Noncentrosymmetric Manganese Bismuth Thiocyanate Perovskites

This is the authors' abstract. We don't add key points for this paper.

Symmetry-lowering orderings in perovskites can produce a wide range of functions. Thiocyanate based perovskites, AM(SCN)3, have orderings distinct from those of the atomic oxides, enabling new functional behavior. We report four new defect-ordered manganese thiocyanate perovskites K{Mn[Bi(SCN)6]},NH4{Mn[Bi(SCN)6]}·18H2O,Cs{Mn[Bi(SCN)6]}·18H2O, and Gua6{Mn9[Bi(SCN)6]8}·6H2O, and solve their structures using a combination of powder X-ray, single crystal X-ray, single crystal electron and single-crystal neutron diffraction combined with solid-state 1H, 13C, and 133Cs MAS NMR. These frameworks each adopt a structure distinct from both previously reported thiocyanates, and other molecular and atomic perovskites. These noncentrosymmetric thiocyanate perovskites demonstrate how frustration between octahedral tilts and A-site ordering can produce complex function.