Computational determination of the electronic structure, optoelectronics, thermodynamics and nonlinear optical properties of undoped and doped pentacene and tetracene

Ab-initio and density functional theory (DFT) computational study of the effect of fluorine on the electronic, optical, thermodynamic, hole and electron transport properties of the circumanthracene molecule

“…The phenomenon of nonlinear optics has great potential in the field of optical telecommunications and optical information storage. The theoretical determination of first hyperpolarizability and dipole moment are very useful in understanding the relationship between molecular structure and nonlinear optical properties [ 48 ]. The space group for the undoped molecule is D 2h , while for the doped molecules are C 2V .…”

“…The second hyperpolarizability (γ) for all studied molecules is maximal on the B3LYP/cc-pVDZ method and then on the BPBE/cc-PVDZ method. For a given molecular system, when the values of the first hyperpolarizability (β mol ) and dipole moment (μ) are higher than those of urea (μ = 3.8851D and β mol = 372.8 × 10 −33 esu), the said molecule has very good nonlinear optical properties [ 48 , [51] , [52] , [53] ]. The calculated values of β mol and μ, for the molecules C 40 F 16 and C 40 H 10 F 6 , are much higher than those of urea, regardless of the method used.…”

Size Isn’t Everything: Geometric Tuning in Polycyclic Aromatic Hydrocarbons and Its Implications for Carbon Nanodots

“…We make special note that HOMO–LUMO gaps are not rigorously connected to the first excitation energy. − However, they are commonly used as a proxy and can be justified as an acceptable approximation. , The magnitude of the HOMO–LUMO gap is dependent on the functional chosen. , HOMO–LUMO gaps from hybrid approximations like ωB97x-D tend to overpredict the excitation energy significantly and require heuristic corrections. − The ground-state geometry HOMO–LUMO gap (HL@S 0 ) is a good first-order approximation for excitation energy trends but is not suitable for emission energies as it neglects vibrational relaxation in the excited state. The vibrational relaxation red shift is accounted for in excited-state geometry HOMO–LUMO gaps (HL@S 1 ), making them a better approximation to emissions energy trends.…”

Readout of Oriented Triplet Excitons in Linear Acenes via Room-Temperature Electrically Detected Magnetic Resonance

“…The singlet-fission dynamics of Tc/Pc blends have been studied, and it was observed that both acenes undergo homofission with a small contribution from heterofission between each species. 31,56,57 It was reported that even at low Pc guest concentrations, the triplet exciton population was dominated by those localized on Pc on a time scale of 10−100 ps. 55 Detection of triplet spins can be accomplished by driving triplet sublevel transitions with microwaves through a variety of magnetic resonance techniques.…”

“…It also possesses a crystal structure identical to that of Pc, making clean substitutional doping of Tc crystals with Pc guests possible. − In this host–guest architecture, the Tc host is directly optically excited to induce SF, while the Pc acts as a triplet acceptor and trap site. The singlet-fission dynamics of Tc/Pc blends have been studied, and it was observed that both acenes undergo homofission with a small contribution from heterofission between each species. ,, It was reported that even at low Pc guest concentrations, the triplet exciton population was dominated by those localized on Pc on a time scale of 10–100 ps …”