| Abstract
| - Electrochemical studies of polymetallorotaxane films of a general formula poly[1,3,Mn+] where Mn+ is copper(I), cobalt(II), zinc(II), or lithium(I) are reported for both metalated and demetalated (poly[1,3,-]) forms.Cyclic voltammograms (CV) recorded for polymetallorotaxanes containing redox-active metals, with anexception of the Li one, in addition to the electroactivity of the complexing metal exhibit two redox couplesassociated with the consecutive oxidation/reduction of the oligothienylene units in the wiring polymer. Forpoly[1,3,Cu+], the CV studies are completed by ESR spectroelectrochemical investigations combined within-situ conductivity measurements as a function of the electrode potentials. In the ESR response, two signalsof different origin can be distinguished: a broad signal originating from Cu(II) paramagnetics ions (ΔHpp ofca. 265 G) and that due to unpaired spins of the polymer backbone (ΔHpp of ca. 21 G). Potential dependenciesof these two signals as well as potential-induced conductivity variations are consistent with the postulate oftwo independent conductivity processes occurring via mixed-valence Cu(II)/Cu(I) moieties and throughbipolaron-type charge carriers. For comparison, ESR and conductivity responses to the working electrodepotential change were measured for poly[1] and poly[2], i.e., thienylene unit-based polymers constitutingwiring backbones in the polymetallorotaxanes studied. The comparison of these results clearly indicates thatmetal-complexed rings constitute barriers which lower charge-carrier mobility. As a result, poly[1] and poly[2] exhibit significantly higher electronic conductivity (σ of ca. 5 × 10-3 S/cm) as compared to the conductivityof the corresponding polymetallorotaxanes (σ of ca. 2 × 10-5 S/cm).
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