The effect of irradiation-induced disorder on the conductivity and   critical temperature of the organic superconductor   $\kappa$-(BEDT-TTF)$_2$Cu(SCN)$_2$
  We have introduced defects into clean samples of the organic superconductor $\kappa$-(BEDT-TTF)$_2$Cu(SCN)$_2$ in order to determine their effect on the temperature dependence of the conductivity and the critical temperature $T_{\rm c}$. We find a violation of Matthiessen's rule that can be explained by a model of the conductivity involving a defect-assisted interlayer channel which acts in parallel with the band-like conductivity. We observe an unusual dependence of $T_{\rm c}$ on residual resistivity which is not consistent with the generalised Abrikosov-Gor'kov theory for an order parameter with a single component, providing an important constraint on models of the superconductivity in this material. 
James G. Analytis, Arzhang Ardavan, Stephen J. Blundell, Robin L.   Owen, Elspeth F. Garman, Chris Jeynes and Ben J. Powell