Methanol Dynamically Activated Room-Temperature Phosphorescence from a Twisted 4-Bromobiphenyl System

Abstract

Crystal engineering is employed widely in developing metal-free room-temperature phosphorescence (RTP) materials, but the weak responsiveness in rigid state and poor selectivity during crystallization limit the research of RTP materials with specific recognition properties. Herein, based on multicomponent crystallization and the deformation of phosphor, we have developed a galactose-functionalized polyhydric compound (BHB) with a twisted 4-bromobiphenyl structure, to realize methanol selectively activated "off-on" RTP system. Methanol molecules selectively formed solvate with BHB and rigidified the crystal structure by enriching intermolecular noncovalent interactions. Meanwhile, the distortion of the biphenyl group facilitated the intersystem crossing process effectively, alongside the heavy-atom effect from the bromo substitute, thereby, activating the RTP of BHB. Thus our current research approach realizes RTP materials with selective recognition function by controlling multiple noncovalent interactions such as hydrogen and halogen bonding of molecular systems with structurally distorted phosphors.

Highly Efficient Room‐Temperature Phosphorescence Based on Single‐Benzene Structure Molecules and Photoactivated Luminescence with Afterglow

“…More importantly, all the phosphor exhibited a high SOC value (Table S2, Supporting Information, <S 1 |H SO |T n >), [26] which were calculated by a simplified method by selecting the geometry of the excited state. [5] And such high SOC, which should be attributed to the presence of carbonyl, would tremendously enhance the ISC yield. The strong ISC might explain the low Ф F and high Ф P of those compounds.…”

“…Metal-free room-temperature phosphorescence (RTP) emission materials, characterized by large Stokes shift and long lifetime, [1,2] have potential in triplet sensitizer for chemical synthesis, [3] anti-counterfeiting materials, [4] sensors, [5,6] cell imaging, [7,8] and so forth. Taking advantage of the susceptible nature of phosphorescence, many stimuli-responsive RTP materials controlled by various stimulations, like mechanical force, chemical species, humidity, and light have been reported.…”

Modulating Room Temperature Phosphorescence by Oxidation of Thianthrene to Achieve Pure Organic Single-Molecule White-Light Emission

“…Recently, a series of important advances have been made in pure organic RTP materials, [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45] which provide a great opportunity and a solid foundation to develop pure organic SMWLE materials through a combined mechanism of fluorescence and RTP. However, pure organic phosphorescence is commonly observed under rigorous conditions (e.g., cryogenic or vacuum) as a result of spin-forbidden transition of T 1 →S 0 , leading to very rare dual-emission real systems of fluorescence and RTP under ambient conditions.…”

Dual-Responsive Thermally Activated Delayed Fluorescence of Spiropyran Derivatives

“…62 As shown in Figure 2, the highest occupied natural transition orbital (HONTO) and the lowest unoccupied natural transition orbital (LUNTO) of SP1 were orthogonal and almost not overlapped. Although the SOC matrix element value between S 1 and T 1 sate was not satisfied (0.086 cm -1 , Table S2), which was calculated by a simplified method by selecting the geometry of the excited state, 33,63 the small energy difference (0.03 eV) between S 1 and T 1 state could Page 10 of 24 CCS Chemistry This article presented here has been accepted for publication in CCS Chemistry and is posted at the © 2021 Chinese Chemical Society.…”