5. Conclusions
The present UV–vis spectra, magnetic moment measurements, and B3LYP calculations indicate that the CoBr2(pMA)2 complex has three unpaired electrons and distorted tetrahedral environment around the Co ion. NiBr2(pMA)2 complex has distorted octahedral coordination around the Ni atom by sharing two Br atoms of the neighboring complexes, however MnBr2(pMA)2 complex has 5-coordinate polymeric bromide bridged structure around the Mn atom, by sharing one Br atom of the neighbor complex. The Mn complex has five unpaired electrons while the Ni complex has two unpaired electrons. It is also apparent from the vibrational spectra that the coordination occurs via nitrogen atom of pMA in these complexes. Thermal decomposition studies showed that the complexes decompose in a two-step mass loss reaction and intermediate metal complexes are formed during their decomposition processes. The first removed parts of the complexes with temperature increases have organic contents and thus belong to the ligand pMA.