Syntheses and crystal structures of two supramolecular isomers of manganese(II) with 3,5-bis(isonicotinamido)benzoate

Two new supramolecular isomeric complexes Mn(BBA)₂(H₂O)₂] _n · 4nH₂O (1) and Mn(BBA)₂(H₂O)₂] · 4H₂O (2) were obtained by hydrothermal reactions of MnCl₂ · 4H₂O with 3,5-bis(isonicotinamido)benzoic acid (HBBA) under different ratio of NaOH/HBBA. Complex 1 is a 1-D zigzag chain in which the Mn(II) is six-coordinate with distorted octahedral geometry. The 1-D chains are further connected by hydrogen bonds to give a 3-D supramolecular framework. Complex 2 is a monomeric molecular complex, assembled through intermolecular hydrogen bonds into a 3-D supramolecular network. Reaction conditions have remarkable influence on the structures of the complexes. The thermal and non-linear optical properties of the complexes were studied.