Organometallic cyanotype: formation of Prussian blue by a photochemical decomposition of the arene iron complex

Complex salt [(C₅H₅)Fe(C₆H₆)]₃[Fe(CN)₆] was synthesized and studied by X-ray diffraction. This salt was transformed into Prussian blue pigment upon the irradiation by visible light, which makes this reaction applicable to a photocopying (cyanotype) process.