Coumarin and Hydroxyl Decorated Viscosity Sensitive Triphenylamine Derivatives: Synthesis, Photophysical Properties, Viscosity Sensitivity, TD‐DFT, and NLO Properties

Abstract

Three novel hydroxyl substituted and triphenylamine sidearm coumarin decorated molecules were prepared to examine the effect of adjacent hydroxyl substituent as well as coumarin units on the photophysical linear and nonlinear optical properties. Both hydroxyl function adjacent to the phenyl ring and extra coumarin unit is attributed to the red shifted absorption (435‐487 nm) and emission (496‐578 nm) compared to the plain triphenylamine based coumarin derivatives. Positive solvatochromism around 70 nm was observed in solvents with different polarity polarities and it is reinforced by solvent polarity plots and multilinear regression study. Very high viscosity induced emission enhancement (5.7 – 8.2 fold) was observed for in ethanol/polyethylene glycol‐400 system, highlighting their capability to act as efficient fluorescent molecular rotors (FMRs). The nonlinear optical properties were investigated by solvatochromism as well as a computational method using B3LYP 6–311++G (d, p) basis set. All these compounds exhibited large magnitudes of first order (65‐208x10 −30e.s.u) and second order (560‐2120x10 −36e.s.u) hyperpolarizability.

Charge Transfer Parameters, Correlative Perturbation Potential with Non‐Linear Optical Properties of Bi‐Heterocyclic Dyes Having TCF Acceptor‐ DFT Approach

“…We do not observe any substantial difference in between highly polar solvents such as DMF/ACN. All the BLA values are closer to zero i. e. cyanine limit (BLA=0 Å, BOA=0) [21,38] . BOA are negative and nearing to polyene limit [21,38] which indicates these compounds can be good NLOphoric material.…”

“…All the BLA values are closer to zero i. e. cyanine limit (BLA = 0 Å, BOA = 0). [21,38] BOA are negative and nearing to polyene limit [21,38] which indicates these compounds can be good NLOphoric material. BLA and BOA values are gathered in Table 3 and Table SI 7.…”

“…The asymmetric ICT in D-π-A based molecules lead to large second order hyperpolarizability (γ). [21] The dipole moment and polarizability are also the important factors which influence the NLO properties. [22] Analysing various structural-molecular and NLO properties by experimental method is costly and requires lots of chemicals and instrumentations than the computational methods.…”

“…The asymmetric ICT in D‐π‐A based molecules lead to large second order hyperpolarizability (γ) [21] . The dipole moment and polarizability are also the important factors which influence the NLO properties [22] …”

Investigating the role of corrole as an excitation energy relay in light‐induced processes in closely connected N,N'‐bis(biphenyl‐4‐yl)aniline functionalized corrole donor–acceptor dyad

“…Pertaining to artificial photosynthetic systems, even though the presence of TPA as sacrificial electron donor leads to the stabilization of the charge‐separated state due to hole migration, 27 the optical absorption localized majorly at around 300 nm hinders its use as a panchromatic dye. To address this, and transform TPA into a broad wavelength range absorber, the core of the molecule has been integrated with chromophores such as porphyrin, 27–37 corrole, 38,39 phenothiazine, 40 carbazole, 41 subphthalocyanine, 42 borondipyrromethene (BODIPY), 43–47 azaBODIPY, 48,49 metal complexes, 50,51 heterocyclics such as quinoxaline, 52 thiophene, 53 pyrrolopyrrole, 54 aryldiimides, 55–58 and various light‐harvesting molecules imposing potential applications in DSSCs, 20–23,26,56 OSCs, 17–19 and sensors 59–63 were prepared.…”