The present work is concerned with Mössbauer spectra and magnetic properties of some sixcoordinated complexes of Fe(II) dichloride with bis-diimine (2 or 3-pyridyl imines, C5H4NCR1=NR2 ; R1 = H, CH3, C6H5 ; R2 = C6H5, C6H4CH3, C6H4Cl). For the 2-pyridyl imine complexes, the electronic ground state of Fe(II) changed from high-spin state to the intermediate-spin state when H is replaced by CH3 or C6H5 at R1. However, we found no effects of the replacement of C6H5 by C6H4CH3 or C6H4Cl at R2 on the spin state of Fe(II). In addition, Mössbauer spectra showed two doublets with about 1 : 2 ratio of quadrupole splittings and similar isomer shifts. This suggests that the cis- and trans-stereoisomers are present at low temperature. The 3-pyridyl imine complexes of Fe(II) are all in the high-spin state for any substituents in R1 and R2 groups.
