The structure-directing influence of guanidinium cations in the crystal structures of [C(NH2)3]2[MII(H2O)4(VO3)4] · 4H2O (M = Mn, Co, Ni)

The combination of guanidinium, vanadate and the divalent transition metals MnII, CoII and NiII in aqueous solution leads to the generation of crystals of formula [C(NH2)3]2[MII(H2O)4(VO3)4] · 4H2O (M = Mn, Co, Ni). The structures consist of undulating anionic [MII(H2O)4(VO3)42-] sheets which stack in an ABAB fashion. Guanidinium ions bind pairs of sheets together by a combination of electrostatic attraction and hydrogen bonding to generate a 3D coordination/hydrogen-bonded network. TGA studies of the compounds reveal that upon heating, water molecules are first lost and this process is followed by the decomposition of the guanidinium ion.

Graphical abstractThe combination of guanidinium, vanadate and the divalent transition metals MnII, CoII and NiII in aqueous solution leads to the generation of crystals of formula [C(NH2)3]2[MII(H2O)4(VO3)4] · 4H2O (M = Mn, Co, Ni). The structures consist of undulating anionic [MII(H2O)4(VO3)42-] sheets which stack in an ABAB fashion. Guanidinium ions bind pairs of sheets together by a combination of electrostatic attraction and hydrogen bonding to generate a 3D coordination/hydrogen-bonded network.Figure optionsDownload full-size imageDownload as PowerPoint slide