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Science China Chemistry 2024年第6期67卷 1922-1928页

作者： Shasha Zhang Wei Yao Anqi Lv Kun Liu Yusheng Zhang Chifeng Zhou Huili Ma Huifang Shi Zhongfu An Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing211816China

High-efficiency long-wavelength phosphorescence emissions of large singlet-triplet energy gap(ΔE_(ST))materials are essential for applications in biology and display.However,few long-wavelength phosphorescence emissions of largeΔE_(ST)materials have been reported due to the weak spin-orbit coupling(SOC)and strong non-radiative transitions.Herein,we develop a strategy to achieve highly efficient long-wavelength room temperature phosphorescence(RTP)emission of largeΔE_(ST)materials,which display bright red RTP emission with above 400μs lifetime and 6.5%phosphorescent quantum efficiency.Our experiments and theoretical calculations reveal that the fishbone-like packing and the zig-zag interactions provide favorable conditions for suppressing the non-radiative transitions of triplet state excitons,and heavy atoms effectively promote the intersystem crossing(ISC)process for highly efficient long-wavelength phosphorescence emission.The universality of the method for highly efficient long-wavelength RTP emission of largeΔE_(ST)materials was further investigated in various guests.Moreover,these materials with largeΔE_(ST)manifest the advantages of large color contrast on the display and utilization potentiality in information encryption.This strategy paves the way for the high contrast display and development of information encryption with RTP emission.

关键词： room temperature phosphorescence singlet-triplet energy gap host-guest doping heavy atom effect red phosphorescence

The heavy atom effect on photocleavage of DNA by mono-hydroxyl halogenated corroles

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Chinese Chemical Letters 2010年第3期21卷 373-375页

作者： Chi Kwong Chang Department of Chemistry The Hong Kong University of Science and Technology

DNA photocleavage properties of halogenated mono-hydroxyl corrole 1-5 were investigated.It was found that these corroles were able to photocleavage supercoiled pBR 322 DNA（SC） into nicked-circular DNA（NC）.The activity of these corroles follows an order of 4>3>2≈1>5.The photosensitized singlet oxygen（Φ;） quantum yield by these corroles also follows that same order,showing the photocleavage activity is related to the heavy atom effect of halogen atoms on corroles.

关键词： Corrole DNA Photocleavage heavy atom effect

Ab Initio and Density Functional Study on the First Hyperpo-larizabilities of Squaric Acid Homologues

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Chinese Journal of Chemistry 2004年第4期22卷 333-339页

作者：付伟伟周立新 College of Chemistry and Chemical Engineering Fuzhou University

The first hyperpolarizabilities of four squaric acid homologues: squaric acid, 1, 2-dithiosquaric acid, 1, 2-diselenosquaric acid and 1,2-ditellurosquaric acid have been calculated using ab initio and DFT methods. The effects of equilibrium geometries. basis set and electron correlation on the first hyperpolarizabilities of these molecules were investigated. The frequency dispersion effect and solvent effect, which are essential to get reliable outputs in comparison to the experimental results, have also been explored. On the basis of these investigations, it is worthy to point out that the heavy atom effect takes effect for these squaric acid homologues.

关键词： first hyperpolarizabilities electron correlation effect frequency dispersion effect solvent effect heavy atom effect

Insight understanding into influence of binding mode of carboxylate with metal ion on ligand-centered luminescence properties in Pb-based coordination polymers

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Chinese Chemical Letters 2021年第8期32卷 2423-2426页

作者： Xusheng Gao Liduo Zhao Meijuan Ding Xiaozu Wang Lu Zhai Xiaoming Ren State Key Laboratory of Materials-Oriented Chemical Engineering and College of Chemistry&Molecular Engineering Nanjing Tech UniversityNanjing 211816China College of Chemical Engineering Nanjing Tech UniversityNanjing 211816China College of Materials Science and Engineering Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

In the crystal engineering area,it is important to clearly demonstrating the relationship of structure and certain functionality.Herein,we present the study of the relationship of structure with phosphorescent nature for two new room temperature phosphorescence(RTP) coordination polymers(CPs).[Pb(FDA)(H_(2)O)](1) and [NH_(3)(CH_(3))NH_(2)(CH_(3))_(2)][Pb_(4)(FDA)_(5)](2),where H_(2) FDA is 2,5-furandicarboxylic acid,have been synthesized by solvothermal method using different solvents and Pb^(2+) sources and characterized by microanalysis,powderX-ray diffraction(PXRD),thermogravimetric(TG),IR and UV-vis spectra.The Pb^(2+)ions adopt bicapped triangle prism coordination sphere in 1 and 2,which are connected together via FDA^(2-) ligands into bilayer structure in 1 while pillared-layer framework in 2.The FDA^(2-) ligands show different bridging modes in 1 and 2,leading to distinct coordination interactions between Pb^(2+) ion and FDA^(2-) ligand in both CPs.Both 1 and 2 emit ligand-centered RTP due to the heavy atom of Pb^(2+) ion,with a lifetime and quantum yield of 0.62 ms and 14.9% in 1 versus 1.69 ms and 15.7% in 2.The emission peak shows significant redshift(79 nm) in 2 regarding 1,which arises from their distinction of coordination interactions between Pb^(2+) ion and FDA^(2-) ligand in both CPs.

关键词： Pb-based coordination polymer Carboxylate binding mode heavy atom effect Room temperature phosphorescence Frontier orbital analysis

Recent progress on pure organic room temperature phosphorescent polymers

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Aggregate 2021年第4期2卷 87-99页

作者： Hao Gao Xiang Ma Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghaiChina

So far,pure organic room temperature phosphorescence(RTP)materials are developing rapidly and have become a research hotspot in the scientific community.They are regarded as valuable resources with great potential for development in many fields,such as biomedicine,information multi-level encryption,smart anticounterfeiting,and so on.Among them,a series of pure organic RTP polymer systems emerged at the right moment based on the excellent properties of polymers such as easy processing,low cost,and good biocompatibility.Furthermore,the huge molecular weight,long-chain intertwined structure,and potential interactions with phosphors of polymers make them a focus for RTP emission.Herein,we describe the development history of this system in detail,explore the necessary factors for highly efficient emission from the phosphorescence emission process,and based on the dual effects of enhancing phosphorescence emission and shortening luminescence lifetime brought by heavy atoms,we summarize the internal mechanism and achievements of various researches from the perspective of heavy atom–containing and non-heavy atom systems.

关键词： heavy atom effect room temperature phosphorescence polymer

Synthesis,Characterization,and Linear and Nonlinear Optical Properties of Phenylene-vinylene Based Chromophores for Singlet Oxygen Generation

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Chinese Journal of Structural Chemistry 2013年第11期32卷 1687-1695页

作者：王淑容汤昌泉郑庆东 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

A series of symmetrical and unsymmetrical phenylene-vinylene （PV） based chro- mophores with the molecular configuration of donor-π-donor （D-g-D） were prepared and characterized. Iodine was first introduced into the Jr-conjugation backbone of the PV based chromophores in order to study the heavy atom effect on their linear absorption, two-photon absorption （TPA） properties, as well as singlet oxygen generation properties. TPA cross-sections of these chromophores were investigated by using the two-photon excited fluorescence method. The unsymmetrical chromophores were found to have larger TPA cross-section values compared to their symmetrical counterparts. For one of the unsymmetrical chromophores with the iodine incorporation, a large TPA cross section value with quenched emission was found. The decreased fluorescence quantum yield of a molecule can be ascribed to the increased intersystem crossing, which is favorable for enhancing the singlet oxygen generation. Therefore, the unsymmetrical PV based chromophores with heavy atom incorporation are promising singlet oxygen sensitizers for the photodynamic therapy application.

关键词： two-photon absorption phenylene-vinylene based chromophore,singlet oxygen generation heavy atom effect