Nanostructured Tetrathiotetracene Iodide Crystals (TTT2I3) are very promising materials for thermoelectric applications, as it was predicted earlier. Initially, we have considered a more simplified onedimensional (1D) physical model. For transport along conductive chains in crystals with rather low purity, the effect of interaction of carriers with the nearest chains is negligible in comparison with the scattering on impurities. For ultra-pure crystals, the effect of impurities on charge transport along a molecular chain becomes rather small, and the effect of interchain interaction stands out. In order to verify these conclusions, a two-dimensional (2D) model is elaborated which explicitly takes into account the weak interaction of carriers with the nearest conductive chains.