Synthesis and crystal structures of four complexes based on Schiff base.

Four new metal–organic complexes of the formula [CrL′Cl2] (1), [CuL′Cl2] (2), [MnL′′Cl2·H2O] (3), and [NiL′′(OH)2·2NO3] (4) [L′=N-(1-Pyrazin-2-yl-ethylidene)-ethane-1,2-diamine, L′′2=N,N′-Bis-(1-pyrazin-2-yl-ethylidene)-ethane-1,2-diamine] have been synthesized and characterized by infrared method, elemental analysis, X-ray powder diffraction analysis, and single-crystal X-ray diffraction techniques. Their heat stability was tested by thermo gravimetric analyzer. X-ray structure analysis reveals that complexes 1–4 are all 0 D structure. The L ligand have many types of coordination modes that make these complexes as having different configuration π–π stackings and/or hydrogen bonding interactions, which seem to be effective in stabilizing these crystal structures. [ABSTRACT FROM AUTHOR]