Rectifying effects in di-block oligomer molecular diodes

Very recently, diode-type I-V characteristics were measured in di-block oligomer molecular diodes. These molecules consist of electron-rich and electron-deficient $\pi $-congugated oligomers that exhibit built-in electronic asymmetry. We will discuss fundamental transport mechanisms in di-block oligomer molecular diodes based on the features of the energy spectrum of the tunneling electron. Green's function theory sub-barrier scattering is applied to predict current-voltage characteristics of these complicated molecules. In particular, the rectifying effects are explained by different energy dependence of scattering operators of thiophene and thiazole structural units.