本文叙述了新建立的磁场效应(Magnetic Field Effects,简称MFE_s)-偏振-共振同步荧光法。利用偏振技术抑制掉溶剂散射光的99％,利用MFE_s抑制溶剂98％的散射光波动。将偏振、MFE_s技术与共振同步荧光法结合为一体时,则大大改善Δλ=0的...本文叙述了新建立的磁场效应(Magnetic Field Effects,简称MFE_s)-偏振-共振同步荧光法。利用偏振技术抑制掉溶剂散射光的99％,利用MFE_s抑制溶剂98％的散射光波动。将偏振、MFE_s技术与共振同步荧光法结合为一体时,则大大改善Δλ=0的共振同步荧光法的检测灵敏度。如蒽、苝舵同时测定时,其检测限分别为0.068ng/ml、0.015ng/ml。优于一般的Δλ值较小(0～5nm)的同步荧光法和偏振-同步荧光法。展开更多
The phenomenon that different molecular packing modes in aggregates result in different optical properties has attracted intense attention,since it can provide useful information to establish the relationship between ...The phenomenon that different molecular packing modes in aggregates result in different optical properties has attracted intense attention,since it can provide useful information to establish the relationship between the micro-and macro-world.In this paper,DBTDO-DMAC was designed with 9,10-dihydro-9,9-dimethylacridine(DMAC)as electron donor.DBTDO-DPA and DBTDO-Cz were designed for comparison,which adopted diphenylamine(DPA)with twisted structure and carbazole(Cz)with planar structure as donors,respectively.As expected,two polymorphs(Crystal G and Crystal Y)of DBTDO-DMAC were obtained and exhibited distinct properties.Crystal G originating from planar conformation exhibited mechanochromism(MC)phenomenon and the emission color changed from green to yellow with a redshift of 35 nm after grinding.Nevertheless,Crystal Y with folded conformation displayed obvious room-temperature phosphorescence(RTP)with yellow afterglow.Careful single crystal analyses,powder X-ray diffraction and theoretical calculation reveal that the different emissive behaviors are highly related to the molecular conformation and packing modes.The successful adjustment of molecular conformation provides some guidance in the design of other MC and/or RTP luminogens,broadens the molecule family with the tunable molecular conformation and opens up a new avenue for exploring possible adjustment of molecular packing in aggregates.展开更多
The luminescence behaviors of 4’-dimethyldrinoflavone derivarive with different structures have been studied in different conditions. Results show that the luminescence behavior depends dramatically on the solvent po...The luminescence behaviors of 4’-dimethyldrinoflavone derivarive with different structures have been studied in different conditions. Results show that the luminescence behavior depends dramatically on the solvent polarity. The reason is attributed to the different conformations in different solvents. The planar conformation is proved to be favorable to the fluorescence emission. In addition, results of viscosity-dependent luminescence property show that for compound 3 with the rigidized planar structure the luminescence behavior do not depend on the medium viscosity. But, for compound 1 and 2 the fluorescence quantum yields increase with increasing medium viscosity evidently,indicating that the rotation relaxation process of benzene ring in the molecule is yery important for the nonradiative decay process of excited molecules of compounds.展开更多
文摘本文叙述了新建立的磁场效应(Magnetic Field Effects,简称MFE_s)-偏振-共振同步荧光法。利用偏振技术抑制掉溶剂散射光的99％,利用MFE_s抑制溶剂98％的散射光波动。将偏振、MFE_s技术与共振同步荧光法结合为一体时,则大大改善Δλ=0的共振同步荧光法的检测灵敏度。如蒽、苝舵同时测定时,其检测限分别为0.068ng/ml、0.015ng/ml。优于一般的Δλ值较小(0～5nm)的同步荧光法和偏振-同步荧光法。
基金the National Natural Science Foundation of China(21875130)the Starting Foundation of Tianjin Universitythe Project of“100 Talents Program”of Shanxi Province。
文摘The phenomenon that different molecular packing modes in aggregates result in different optical properties has attracted intense attention,since it can provide useful information to establish the relationship between the micro-and macro-world.In this paper,DBTDO-DMAC was designed with 9,10-dihydro-9,9-dimethylacridine(DMAC)as electron donor.DBTDO-DPA and DBTDO-Cz were designed for comparison,which adopted diphenylamine(DPA)with twisted structure and carbazole(Cz)with planar structure as donors,respectively.As expected,two polymorphs(Crystal G and Crystal Y)of DBTDO-DMAC were obtained and exhibited distinct properties.Crystal G originating from planar conformation exhibited mechanochromism(MC)phenomenon and the emission color changed from green to yellow with a redshift of 35 nm after grinding.Nevertheless,Crystal Y with folded conformation displayed obvious room-temperature phosphorescence(RTP)with yellow afterglow.Careful single crystal analyses,powder X-ray diffraction and theoretical calculation reveal that the different emissive behaviors are highly related to the molecular conformation and packing modes.The successful adjustment of molecular conformation provides some guidance in the design of other MC and/or RTP luminogens,broadens the molecule family with the tunable molecular conformation and opens up a new avenue for exploring possible adjustment of molecular packing in aggregates.
文摘The luminescence behaviors of 4’-dimethyldrinoflavone derivarive with different structures have been studied in different conditions. Results show that the luminescence behavior depends dramatically on the solvent polarity. The reason is attributed to the different conformations in different solvents. The planar conformation is proved to be favorable to the fluorescence emission. In addition, results of viscosity-dependent luminescence property show that for compound 3 with the rigidized planar structure the luminescence behavior do not depend on the medium viscosity. But, for compound 1 and 2 the fluorescence quantum yields increase with increasing medium viscosity evidently,indicating that the rotation relaxation process of benzene ring in the molecule is yery important for the nonradiative decay process of excited molecules of compounds.
