Spinless charge carriers in divalent cation doped polyacetylene

We report the n-doping of trans-polyacetylene with divalent calcium and europium counter-cations. Optical absorption and electron paramagnetic resonance (EPR) data suggests that pairs of charged solitons are confined by the divalent dopants through Coulomb interactions. This confinement leads to a splitting of the mid-gap soliton level and broadens the width of the EPR signal. The doped films exhibit an increase in conductivity with no corresponding increase in magnetic susceptibility, suggesting that the charged state is still spinless. © 1990.