Mössbauer and magnetic studies of Eu porphyrins (abstract)

We report the first measurements on porphyrin compounds using Eu as the Mössbauer nuclide. There have been many Mössbauer studies on iron porphyrins1,2 and a few on tin.3 We have successfully prepared and made Mössbauer and magnetic susceptibility measurements on four Eu based porphyrin compounds to elucidate the relationship between magnetic properties and structure. Absorption spectra using the 21.6 keV gamma ray of 151Eu were obtained at room temperature and 80 K and yielded very broad singlets with room temperature isomer shift values between 0.20±0.02 mm/s and 0.90±0.02 mm/s with respect to EuF3. Experimental results show the Eu ion to be in the trivalent oxidation state. A discussion of the electronic properties and structure will be reported and compared with previous results found on iron and tin based porphyrins.<ks>