Density Functional Theory Study of Poly(o-phenylenediamine) Oligomers

Abstract

Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have been performed to gain insight into the structure of poly(o-phenylenediamine) (POPD). Both reported structures of POPD, ladder (L)- and polyaniline (P)-like, are investigated theoretically through the oligomers approach. The simulated vibrational properties of 5POPD(L) and 5POPD(P) at B3LYP/6-31G (d) along with their assignments are correlated with experimental frequencies. Vibrational spectra show characteristic peaks for both POPD(L) and POPD(P) structures and do not provide any conclusive evidence. Excited-state properties such as band gap, ionization potential, electron affinities, and HOMO–LUMO gaps of POPD(L) and POPD(P) from monomers to five repeating units are simulated. UV–vis spectra are simulated at the TD-B3LYP/6-31+G (d, p) level of theory, supportive to the ladder-like structure as the major contributor. Comparison of the calculated data with the experimental one strongly suggests that the ladder-like structure is the predominant contributor to the molecular structure of POPD; however, a small amount of POPD(P) is also believed to be present.

Combined experimental and theoretical study of poly(aniline-co-pyrrole) oligomer

“…Advanced functional macromolecules such as conjugated organic polymers (COPs) [1][2][3] are promising due to their wide range of technological applications in the area of rechargeable batteries [4], optoelectronic devices [5], light emitting diodes [6], photovoltaic, sensors [7], biosensors [6,8], electrochromic display material, electromagnetic shielding [9], artificial muscles, and solar cell. Among COPs; poly (o-phenylenediamine) (POPD) [9], poly (3, 4-ethylenedioxythiophene) (PEDOT), polyparaphenylene (PPP), polyparaphenylenevenylene (PPV), polythiophene (PT), polypyrrole (PPy) [10], and polyaniline (PANI) have been studied both theoretically [11,12] and experimentally for efficient synthesis, characterization and applications [13][14][15].…”

Polypyrrole/TiO2 composites for the application of photocatalysis

“…All DFT calculations [28,29] were carried out on GAUSSIAN 09 [30] and the results were visualized through Gabedit [31], GaussSum [32], and GaussView [33]. DFT and time-dependent DFT (TD-DFT) calculations were performed at B3LYP with LanL2DZ basis set for the determination of electronic structure properties of nPy-Ti 16 O 32 , as an efficient photocatalyst.…”

“…DFT and time-dependent DFT (TD-DFT) calculations were performed at B3LYP with LanL2DZ basis set for the determination of electronic structure properties of nPy-Ti 16 O 32 , as an efficient photocatalyst. Oligomers up to eight repeating units can accurately represent its polymeric characteristics so, oligomeric size is restricted to nine repeating units [28,29]. A molecular cluster of Ti 16 O 32 is added to the oligomeric backbone of nPy and then optimized.…”

Donor-acceptor polymer for the design of All-Solid-State dye-sensitized solar cells

“…GAUSSIAN 09 [30] is used for the DFT calculations [31] while the results are visualized through Gabedit [32], GaussSum [33], and GaussView [34]. DFT and time-dependent DFT (TD-DFT) calculations are used for the electronic properties simulations of the mentioned materials, to predict an efficient model for SDSC.…”

“…DFT and time-dependent DFT (TD-DFT) calculations are used for the electronic properties simulations of the mentioned materials, to predict an efficient model for SDSC. Different oligomeric chain lengths of EDOS, BSD and HTM from monomers up to nine repeating are considered and extended to polymers, using second order polynomial fit equation [31]. Prior to property simulations of the interacting systems such as N3-HTM, N3-TiO2, and HTM-N3-TiO2; the DFT method was confirmed through correlation of the HTM simulated HOMO, LUMO and band gaps with experimental data (see Table S1) [28,35].…”