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Transconductance measurements have been used to characterize the space4harge regions of various n-Si/ liquid contacts. To perform these measurements, Si electrodes were photolithographically processed to introduce p+-contact areas into the surface of an n-type Si electrode. The electrical conductance between these p+ regions was then used to probe the minority carrier concentration in the near-surface region of the n-type Si. Unlike conventional differential capacitance or current-voltage measurements, these transconductance measurements can be performed under near-equilibrium conditions and can be performed in the presence of gaseous ambients or when the sample is in contact with ionically conducting electrolyte solutions. In contact with the electrolyte solutions, faradaic and solid-state conduction pathways were distinguished using ac impedance measurements. The impedance spectra provided clear evidence that contact with MezFc (l,l'-dimethylferrocene)+/O and Fc+/O redox couples in CH30H(l)-1.0 M LiC104 formed an inversion layer in the n-Si, but that CH3OH(l)-l.O M LiClO4-MeloFc+/O solutions did not yield an inversion layer. These observations are consistent with prior current-voltage measurements on these junctions. The barrier heights of the n-Si/CH30H-Me2Fc+/O and n-Si/CH30H-Fc+/O junctions were determined to be 1.01 and 1 .e2 V, respectively. These measurements provide new insight into the photoelectrochemical behavior of S I / C H~O H contacts and provide an alternate method for characterizing the energetics of semiconductor/liquid contacts.

Ring opening metathesis polymerization (ROMP) has been used to prepare conjugated polymers that contain ferrocene moieties as part of their backbones. The conjugated polymer poly-(ferrocenylenedivinylene) (PFDV) and the analogous unconjugated polymer poly(ferrocenylenebutenylene) (PFB) with chain lengths of greater than 10 were found to be insoluble in typical organic solvents. The conductivities of oxidatively doped films of PFDV and PFB were found to be 10™4 and ™5 ™1 cm™1, respectively. Oxidative doping of the monomer 1,4-( 1, -ferrocenediyl)-1-butene was found to yield conductivities on the order of ™5 ™1 cm™1, supporting interchain hopping as the dominant mechanism for charge carrier movement through these films. The ROMP of monomers octamethyl-l,4-(l,l'ferrocenediyl)-!,3-butadiene and l,4-(l,l'-ferrocenediyl)-l-methoxy-l,3-butadiene was also studied. Although soluble polymer was successfully generated from the latter monomer, no conditions were found under which the octamethyl compound could be polymerized.

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