02185nas a2200241   4500008004100000022001400041245015900055210006900214260005700283300000800340490000700348520129500355653000801650653003101658653001701689653002001706653001101726100002401737700002001761700001701781700002301798856012201821       2016                        eng d  a1610-294000aDoes the position of the electron-donating nitrogen atom in the ring system influence the efficiency of a dye-sensitized solar cell? A computational study0 aDoes the position of the electrondonating nitrogen atom in the r  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUN  a1210 v223 a<p>We have reported a number of new metal-free organic dyes (2-6) that have cyclic asymmetric benzotripyrrole derivatives as donor groups with peripheral nitrogen atoms in the ring, fluorine and thiophene groups as pi-spacers, and a cyanoacrylic acid acceptor group. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were employed to examine the influence of the position of the donor nitrogen atom and pi-conjugation on solar cell performance. The calculated electron-injection driving force (Delta G(inject)), electron-regeneration driving force (Delta G(regen)), light-harvesting efficiency (LHE), dipole moment (mu(normal)), and number of electrons transferred (Delta q) indicate that dyes 3, 4, and 6 have significantly higher efficiencies than reference dye 1, which exhibits high efficiency. We also extended our comparison to some other reported dyes, 7-9, which have a donor nitrogen atom in the middle of the ring system. The computed results suggest that dye 6 possesses a higher incident photon to current conversion efficiency (IPCE) than reported dyes 7-9. Thus, the use of donor groups with peripheral nitrogen atoms appears to lead to more efficient dyes than those in which the nitrogen atom is present in the middle of the donor ring system.</p>10aDFT10aDye-sensitized solar cells10aOrganic dyes10aPosition effect10aTD-DFT1 aBiswas, Abul, Kalam1 aBarik, Sunirmal1 aDas, Amitava1 aGanguly, Bishwajit  uhttps://library.ncl.res.in/content/does-position-electron-donating-nitrogen-atom-ring-system-influence-efficiency-dye