Density functional theory analysis of electronic and transport properties of functionalized Poly-Pyrrole

The electronic, vibrational and transport properties of Poly-Pyrrole (p-Py) and functionalized p-Py (F-Py) conducting polymers were studied by means of density functional theory and non-equilibrium Green's function method. The electronic properties were studied in terms of HOMO-LUMO and density of state spectra. It divulges that the band gap has shrunk appreciably due to the addition of nitraso and thio functional groups upon the p-Py structure. The variation in the band gap is may be due the half filled 2S orbit of nitrogen atoms in the p-Py structure. Vibrational spectra reveals that there is a shift in the frequency towards the lower region. This may be due to the addition of functional groups in p-Py structure and they are identified due to molecular stretching. Transport properties of p-Py and F-Py are studied by constructing nano devices showed an appreciable hike in current variation from nano amperes to milli amperes by the addition of functional groups. This results are confirmed with the corresponding transmission and PDOS spectra.