2005 年 47 巻 2 号 p. 140-146
Much attention has been paid to the spin crossover process since the process is closely connected with the enzymatic pathways involving the heme proteins. The full picture of the spin crossover process is, however, not yet clarified. This paper describes our recent finding on the novel spin crossover process between S=3/2 and S=1/2 in highly saddled iron (III) porphyrin complex [Fe (OETPP) (Py) 2] ClO4, which was directly monitored by the crystallographic analysis at 298, 180, and 80 K.