DIMERIC NATURE OF HEMIN HYDROXIDES

The hematins derived from tetraphenylporphine and deuteroporphyrin IX dimethyl ester have been found to be dimeric in methylene chloride by molecular weight measurements. Infrared studies indicate the presence of iron-oxo-iron bridges in both systems. The room-temperature magnetic moment of one, the µ-oxo-bis(tetraphenylporphineaquoiron(III)), was found to be 1.74 BM per iron. The results of previous magnetic studies for hematins are interpreted as due to mixtures of high-spin hydroxo monomers and low-spin oxo dimers. The difference between the Mössbauer spectra of hemins and hematins is discussed. © 1969, American Chemical Society. All rights reserved.