Unveiling the Photophysical Properties of Boron Heptaaryldipyrromethene Derivatives

Abstract

Increased interest has been devoted to the discovery of multifunctional materials with desirable properties, as continuous performance enhancement of various devices mainly depends on high-performance materials. Now, density functional theory has become a powerful tool to design new materials and rationalize experimental observations. In this work, we explored the photophysical properties origin of chiral boron heptaaryldipyrromethene (heptaaryl-BODIPY), which has charming optoelectronic properties. At the same time, we designed the other five compounds on the basis of heptaaryl-BODIPY. The simulated electronic absorption and emission spectra of heptaaryl-BODIPY are in agreement with experimental ones, allowing us to reliably assign its electronic transition property. The designed compound 6 shows remarkably large first hyperpolarizability value up to 82.78×10 esu. For this kind of compounds, their NLO response values associate with not only position but also electronic nature of substituent groups. Moreover, electron reorganization energies of compounds 1-4 are comparable to tris(8-hydroxyquinolinato)aluminium(III) which is a typical electron transport material. Intriguingly, the studied compounds are the excellent fluorescent probe materials from the standpoint of large Stokes shift and high emission efficiency. Our work enables an opportunity for understanding the relationship between microelectronic structure and macroscopic performance of BODIPY derivatives.

Unveiling the Photophysical Properties of Boron-dipyrromethene Dyes Using a New Accurate Excited State Coupled Cluster Method

“…Quantum chemistry can answer some of these questions by exploring the chemical and photochemical properties of BODIPY dyes, such as their luminescence spectra or the fluorescence/phosphorescence ratio. − However, the most commonly used functionals applied within the framework of time-dependent density functional theory (TD-DFT) are not able to reproduce the photophysical properties of BODIPY dyes. , Several groups have overcome this difficulty by using other methods like SOS-CIS­(D) and CASPT2 , or using purpose-specific functionals. , These solutions are unfortunately not a panacea as SOS-CIS­(D) results rely on the quality of the underlying CIS calculation while CASPT2 requires an active space and suffers from the intruder state problem. Thus, an accurate theoretical method which is capable of delivering results of a uniform quality in a black box fashion and without such deficiencies is much desired for the study of larger molecules such as BODIPY compounds.…”

DFT study of effect of substituents on second-order NLO response of novel BODIPY dyes

“…Up to now, the density functional theory (DFT) was successfully applied to calculation of NLO properties of various derivatives, for example, carborane derivatives, organometallic complexes and so on [40][41][42][43][44]. Therein, the NLO properties of molecules that contain BODIPY section have been investigated by several groups [28][29][30][45][46][47]. For example, Misra [45] have reported a theoretical study of tuning second-order NLO response of a series of aryl-substituted boron-dipyrromethene dyes, manifesting incorporation of various D/A groups in the phenyl ring with BODIPY can affect the ICT process, ultimately alter the NLO properties.…”

“…For example, Misra [45] have reported a theoretical study of tuning second-order NLO response of a series of aryl-substituted boron-dipyrromethene dyes, manifesting incorporation of various D/A groups in the phenyl ring with BODIPY can affect the ICT process, ultimately alter the NLO properties. Liu et al [46] have explored the NLO properties origin of chiral boron heptaaryldipyrromethene compounds with the aid of DFT calculations. The results indicated that the compounds with the large first hyperpolarizability values will to be the excellent candidates for the second-order NLO materials.…”