Chirality and magnetism in a novel series of isotypic borophosphates: M(II)[BPO4(OH)2] (M(II) = Mn, Fe, Co)

Three novel isotypic borophosphates M(II)[BPO4(OH)2] (M(II) = Mn, Fe, Co) have been hydrothermally synthesized and structurally characterized. The isotypic compounds crystallize in the chiral space group P3(1)21 or P3(2)21. Their crystal structures are characterized by edge-sharing helical M(II)O6-octahedral chains wound around 3(1) or 3(2) screw axes (along [001]) interconnected by borophosphate single chains of alternating BO2(OH)2 and PO4 tetrahedra perpendicular to [001], resulting in three-dimensional framework structures. The helical M(II)O6-octahedral chains lead to low-dimensional magnetic properties.