Electronic properties of thienylene vinylene oligomers: synthesis and theoretical study

Multiscale Approach to the Study of the Electronic Properties of Two Thiophene Curcuminoid Molecules

“…In this work, we consider the B3LYP hybrid functional, consistent with B3 Becke's three‐parameter exchange correlation functional, and the Lee, Yang, and Parr LYP correlation functional that recovers the dynamic electron correlation . This choice was made by consideration of our previous work with conjugated molecules. The well‐known popularity of the B3LYP functional within the theoretical community is due to calculations with results that are comparable to most post‐Hartree–Fock methods but obtained in a faster way.…”

“…A two‐step procedure previously used was implemented to resolve the geometry and energy of the ground state for the several hypothetic conformers of the 2‐thphCCM ( 1 ) and 3‐thphCCM ( 2 ) compounds, both in the gas phase and in solvent, considering the Tomasi polarized continuum model (PCM) to account for the effect of the dichloromethane solvent used in UV/Vis experimental spectra. The vertical S 0 →S n ( n =1 to 5) singlet–singlet transitions corresponding to absorption spectra of each of the 2‐thphCCM and 3‐thphCCM oligomers were resolved by time‐dependent DFT (TD‐DFT/B3LYP/6–311G+(d,p)) calculations including the solvent effect. The electronic densities of the HOMO and LUMO states were also obtained.…”

“…In this work, we consider the B3LYP hybrid functional, consistent with B3 Becke's three-parameter exchange correlation functional, and the Lee, Yang, and Parr LYPc orrelation functional that recovers the dynamic electron correlation. [24] This choice wasm adeb yc onsideration of our previous work [25,26] with conjugated molecules. The well-known popularity of the B3LYP functional within the theoretical community is due to calculations with resultst hat are comparable to most post-Hartree-Fock methods but obtained in af aster way.O nt he other hand, the 6-311G + (d,p) basis set is the ratherc omplete set of 6-311G functions [27] supplemented with diffuse functions [28] as well as polarization [29] and is used to have ab etter representation of the wave functions of the molecular systems.…”

Effect of regioregularity and role of heteroatom on the chiral behavior of oligo(heteroalkyl thiophene)s

“…The UV–Vis spectra of the monomers (Table 2 and Figure 1A) display, as expected, a remarkable red shift of the absorption maxima of the alkoxy derivatives with respect to the related sulfanyl compounds, with this effect being more evident in the bithiophene compounds (52 vs. 35 nm) and is attributed to higher coplanarity between the thiophene rings induced by the O atom as compared with S. Accordingly, the aromatic conjugation originated by connecting two thiophene rings in the bithiophenic monomers is higher in the alkoxy derivatives (28 nm when passing from TOR* to T2OR* ) with respect to the sulfanyl derivatives (11 nm when passing from TSR* to T2SR* ). However, it has to be noted that a significant electron‐donating ability is also displayed by the sulfanyl monomers compared with the related 3‐alkylthiophene and 3,3′‐dialkyl bithiophene derivatives, exhibiting maximum absorptions at lower wavelengths, 241 39 and 248 nm, 11 respectively.…”

Alkyl Thiophene Vinylene Electropolimerization in C<sub>8</sub>mimPF<sub>6</sub>, Potential Use in Solar Cells

“…Its structure consists of a vinyl bond between thiophene rings, which can reduce the aromatic character of the ring, with a consequent increase in the delocalization of π electrons and the decrease in the rotational disorder between aromatic rings [10]. In short, vinylene thiophene structures provide the following structural characteristics: planarity, capacity charge delocalization by the presence of five conjugated double bonds and stability, fundamental in obtaining electroactive polymer.…”