High-pressure infrared spectroscopic study of the nitric oxide complex of iron(II)-meso-tetraphenyl porphyrinate

The infrared spectrum of iron(II)-meso-tetraphenylporphyrinate (FeTPP(NO)) has been measured as a function of pressure up to 3.1 GPa. The N–O stretching frequency decreases with increasing pressure, as expected for the bonding model for nitric oxide bound to iron in porphyrin complexes. Other peaks in the spectrum show positive pressure dependence.