| Popis: |
Based on the generalized molecular crystal model (GMCM) and theoretical percolation arguments we investigate small polaron hopping transport in 1D disordered systems at high temperatures. Correlation (cr) effects are taken into account. An analytical expression for the temperature dependence of the electrical conductivity, ln sigma(h,cr) similar to T-1/2, is obtained. This result reproduces satisfactorily the experimental data reported for lambda-DNA and for poly(dA)-poly(dT) DNA, considering DNA as a one-dimensional disordered molecular wire in which small polarons are the charge carriers. ln sigma(h,cr) versus T-1/2 plots permit the evaluation of the maximum hopping distance. The results indicate that correlation effects are probably responsible for large hopping distances in DNA samples. |
