Measurements
The electronic absorption spectra of the solid samples were obtained immersing the material in carbon tetrachlo- ride using a quartz cell with 1 mm path length. The equip- ment used was a Beckman DU 640 spectrophotometer.
The electrochemical measurements were made with an electrode prepared by mixing graphite (Fluka), 50 wt%, and SiIm/CoPc, 50 wt%, and a mineral oil as a binder. This electrode was used as the working electrode, the reference was the saturated calomel electrode, SCE, and a platinum wire was used as the counter electrode. All measurements were made in a electrochemical cell under nitrogen atmos- phere. The equipment used was the potentiostat/gal- vanostat PAR 273 A, from EG&G.