Systematic prediction of new ferroelectrics in space group P3

The current release of the Inorganic Crystal Structure Database contains a total of 57 entries under space group P3 that correspond to 50 different materials. There are 21 structures reported with this space group that satisfy the criteria for ferroelectricity, at a confidence level that depends on the reliability of the underlying structural determination. One ferroelectric discovered earlier is also listed. In addition, the database contains 19 entries that probably should be assigned to a centrosymmetric space group, seven that are polar but probably not ferroelectric and two that are without atomic coordinates. Seven entries are either duplicates or present additional structural studies of the same material. Structures in space group P3 identified as potentially new ferroelectrics include LiAsCu_0.93, Na₂UF₆, BiTeI, BaGe₄O₉, α-UMo₂O₈, Cu₂SiS₃, Co(IO₃)₂, Sr₇Al₁₂O₂₅, KSn₂F₅, YbIn₂S₄, Na₅CrF₂(PO₄)₂, Sn(ClO₂)₂(ClO₄)₆, Eu₃BWO₉, Li(H₂O)₄­B(OH)₄·2H₂O, Mn₃V_1/2(SiO₄)O(OH)₂, Ca₆(Si₂O₇)(OH)₆, Na_6.9(2)[Al_5.6(1)Si_6.4(1)O₂₄](S₂O₃)_1.0(1)·2H₂O, BaCa₂In₆O₁₂, Ni(H₂O)₆[Sb(OH)₆]₂, Sr₄Cr₃O₉ and Cu₅O₂(VO₄)₂·CuCl₂.