  Polaron formation in quasi-one-dimensional organic ferromagnets is studied
based on an extended Su-Schrieffer-Heeger model combined with a Kondo term. The
charge distribution of the polaron is found to be highly asymmetric under
spatial reflection, due to the spin radicals. On the contrary, the spin density
is nearly symmetric; the spin asymmetry introduced by the extra electron
inducing the polaron formation is nearly compensated by the spin polarization
of the lower-energy states. We discuss these results on the basis of real-space
mean-field calculations and symmetry arguments.
