桥链七甲川菁的合成及光性能

菁是一种具有多功能用途的染料,除用作卤化银感光材料及有机光导材料的光谱增感剂、光记录材料中记录介质外,还可作为染料激光器中用的激光染料.我们曾合成了四甲川苯乙烯菁、五甲川(艹粦)及五甲川吡喃鎓等红外染料作为激光染料,测定了它们的光性能.本文合成了具有桥链的七甲川菁,研究了这些桥链七甲川菁的吸收光谱及荧光光谱,并以YAG激光倍频(532nm)作泵浦源,测定了它们的激光调谐范围、中心波长及激光转换效率.     

新型可聚合激光染料及双发色团共聚物的合成

通常染料激光的工作介质是染料溶液,因而限制了在一些技术领域的应用.因此近年来人们将研究兴趣转移到固体激光染料[1～3].激光染料的固体基质相对于其液体溶液存在着显著的技术优势:紧密性、可加工性、无毒、不易燃、无蒸发、易于器件集成化等等.聚合物或硅胶均可用作激光染料的固体基质,用作基质的聚合物与激光染料有很好的相容性,光均一性,且其制作成本低廉.近期报道将激光染料与甲基丙烯酸甲酯进行共聚得到了性能优良的固体激光材料[4],由于激光染料与聚合物链直接相连,减少了耗能,避免了染料过快的降解,大大提高了其光稳定性和激光输出…     

染料掺杂有机改性硅酸盐的制备与光谱特性

1988年Pavlopoulos等人发现1,3,5,7-四甲基吡咯亚甲基BF₂化合物是一个性能优良的激光染料^[1].它的荧光量子效率高,激光效率比香豆素540A高10%,并具有低的三重态吸收和高的光化学稳定性.因此,在染料激光、生物荧光探针、光动力疗法等方面都有潜在的应用背景^[2~4].     

香豆素酮染料光谱性质的研究

近年来,许多具有“推一拉”电子结构的分子内电行转移激光染料的光谱性质的研究引起人们极大的关注[1-5]．研究染料在不同条件下光物理性质行为不仅具有重要的理论意义,而且使激光染料能有效地应用于光功能材料．香豆素酮染料作为一种重要的激光染料,已经在光聚合、光固化等领域中得到广泛应用[6,7]．在这类化合物中不同位置的取代对其光物理性质的研究已有报导[8,9],但香豆素酮染料在不同的非质子传递溶剂中的光物理行为的研究至今未见报导．鉴于以前关于香豆素染料文献报导常涉及到用醇、水等质子传递溶剂,为了避免溶剂与溶质间的氢…     

含吡喃鎓端基的苯乙烯染料合成及电子吸收光谱

多甲川染料已广泛用于银盐感光材料、电子照相、染料激光器、光记录介质及太阳能转换体系等方面。其中苯乙烯多甲川染料具有宽的吸收光谱,引起人们的重视。我们曾合成了含吡喃鎓多甲川染料,它们与含氮杂环的多甲川染料相比,吸收波长红移,并具有极好的光化学稳定性。本文合成了含吡喃鎓端基的二甲川及四甲川苯乙烯染料,测定了电子吸收光谱。     

掺杂酞菁铝的SiO2凝胶荧光特性研究

酞菁类化合物种类繁多,具有良好的光、热稳定性和耐酸、碱等性能,科学家们通过研究发现其优良性能在导电性、光化学催化性、光电效应、液晶显示、气体敏感效应、光疗药物、光变色乃至非线性光学材料等方面具有广泛的应用[1～4].光学上使用的染料一般是液态的,这在很大程度上受到了限制.若将染料分子掺杂到固体基质中无疑会大大增加其使用范围,由于染料在高温下易挥发与分解,因此,传统的熔融玻璃几乎不能作为其载体.为了获得全固化的光学器件,人们试图把有机光学功能分子复合到无机玻璃基质中,溶胶-凝胶工艺是实现这一复合的有效途径之一.利用该工艺人们已经成功地制成了许多富有潜力的复合光功能材料[2].     

BODIPY-吡咯类荧光染料的合成及光谱识别性能

采用Knoevenagel反应以氟化硼配位二吡咯甲川类荧光染料BODIPY(4,4-difluoro-4-bora-3a,4adiaza-s-indacene)为母体,经吡咯甲醛或杯吡咯甲醛合成了四个BODIPY荧光染料1a~1d,用MS,NMR和元素分析进行结构确证。考察了它们的紫外吸收光谱与荧光发射光谱,结果表明1a~1d具有较高的摩尔吸光系数,在BODIPY母环的3,5位双取代物(1c和1d)相对于单取代物(1a和1b)其最大吸收波长和发射波长分别红移了约90nm和80nm,说明BODIPY-吡咯衍生物中共轭程度增强,光谱出现红移。阴离子识别研究表明,1b和1d能够与Cl-形成多重氢键,导致吸收光谱红移和荧光猝灭。     

3-吗啉基氟化硼络合二吡咯甲川类化合物的合成及反应机理研究

以对羟基苯甲醛和吡咯为原料,合成了3-吗啉-8-[4'-(3-吗啉丙氧基)苯基]氟化硼络合二吡咯甲川和3-吗啉-8-(4'-甲氧基苯基)氟化硼络合二吡咯甲川,其结构经过1H NMR和LC-MS分析表征,通过相似性试验和晶体的培养对吗啉直接取代氟化硼络合二吡咯甲川(BODIPY)类化合物3-H的反应机理进行研究.     

含稠合外环的氟硼荧染料类pH荧光探针的研究

以环己醇为起始原料,首先经过改进的三步法制备出2-乙氧羰基-3,4-四亚甲基吡咯,并用过量氢化铝锂高温还原得到2-甲基-3,4-四亚甲基吡咯;再将其分别与4-二甲氨基苯甲醛、4-羟基苯甲醛、4-甲氧基苯甲醛、苯甲醛、4-醛基苯并冠-5等芳醛衍生物在三氟乙酸的催化作用下发生缩合反应,用2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)氧化并依次用N(Et)3和BF3.OEt2处理后得到5种新型含稠合外环的BODIPY类染料衍生物。研究了它们的吸收和发射光谱,并采用荧光光谱滴定方法研究了它们在CH3OH-H2O(1∶1,V/V)中对pH的响应能力。结果表明:BODIPY 1和2在可见光激发下,可以分别作为酸、碱环境下的pH荧光探针并且这两种荧光探针在荧光"开/关"状态之间的转化可以通过质子化和去质子化的方式调控。另外,还初步探讨了荧光探针的设计原理及传感机制。     

高度可溶聚苝酰亚胺材料的合成及性能研究

聚酰亚胺是一类具有优异综合性能的聚合物材料 [1,2 ] .近年来 ,合成含荧光染料的可溶性聚酰亚胺材料在聚合物化学领域引起了广泛兴趣 [3～ 11] ,人们期望这类聚合物材料会比其小分子材料具有更加优越的性能 .小分子酰亚胺荧光染料具有极高的荧光量子效率、光化学和热稳定性 ,可广泛应用于光学开关[12 ] 、电致发光器件 [13,14 ] 和太阳能转换器 [15] 等领域 ,但是由于的大π键平面共轭结构 ,使得材料的溶解性能极差 ,难以加工 .最近 ,本实验室通过合成含叔丁基的芳香二胺 [4,4′-亚甲基双 ( 2 -叔丁基苯胺 ) ]与各种芳香四酸二酐反应…     

8位取代吡咯甲川-BF2化合物的光物理行为

Six novel pyrromethene BF2 complexes,of which five compounds have not been reported,were synthesized and characterized.Their relationships between st ructure and photophysical behavior were studied with the aid of fluorescence and triplet state absorption spectra.The results indicate that,compared to 8 alkyl pyrromethene BF2 complexes,the compounds containing 8 aryl exhibit high fluore scence quantum yield and rather low triplet state absorption.     

Molecular photonics of polymethine dyes in complexes with cucurbit[7, 8]urils

Thiacarbo- and thiadicarbocyanine indolenine and thiazoline polymethine dyes form host?guest complexes with cucurbit[7,8]urils in water. Cucurbit[7]uril forms preferentially 1: 1 and 1: 2 monomeric complexes and cucurbit[8]uril forms 2: 1 and 2: 2 dimeric complexes. On the basis of quantum-chemical calculations, the structure of monomeric and dimeric complexes has been suggested. The complexation manifested itself in absorption, prompt and thermally activated delayed fluorescence spectra, as well as in the triplet?triplet absorption spectra. Dimeric complexes in the triplet state are involved in one-electron oxidation and participate in triplet?triplet energy transfer.     

稀土配合物（RE（DBM）3，RE=Nd、Sm、Gd）分子内能量弛豫过程的光声光谱研究

利用光声振幅谱和位相谱对稀土配合物(Nd(DBM)3、 Sm(DBM)3和Gd(DBM)3分子内弛豫过程进行了研究。Sm(DBM)3、 Gd(DBM)3和Nd(DBM)3的配体π-π*跃迁的光声振幅强度依次增强,而Gd、 Sm和Nd的配合物在配体吸收波段内位相依次减小,反映分子内的弛豫过程。对于Gd(DBM)3,配体最低三重态能量不能传递到中心离子4f激发态能级上而直接弛豫回基态;对于Sm(DBM)3和Nd(DBM)3,配体三重态能量有效地传递到中心离子上, Nd3+各能级间隔小且相互重叠,激发态能量几乎全部以无辐射跃迁回基态; Sm3+为荧光离子,激发态上的部分能量以荧光形式发射。由此并结合荧光光谱的结果建立了分子内能量弛豫模型。     

Spectroscopy and photophysics of dimethyl-substituted alloxazines

We have calculated the electronic structure and absorption spectra from the ground state and the first triplet excited state for five dimethylalloxazines, using the TD-DFT approach. The results of the calculations were correlated to experimental spectral and photophysical data, including the transient spectra reported here containing triplet–triplet absorption data, using the proximity effect theory to explain the variations of the ISC rates with the substitution pattern and solvent. Additionally, singlet oxygen yields were measured for these compounds, demonstrating their high efficiency as singlet oxygen photosensitizers.     

Primary Photoprocesses in Thionine in Supramolecular Complexes with Cucurbit[7,8]urils in Water

Thionine (ThH⁺) molecules form monomeric ThH⁺@CB7 (1: 1) and dimeric 2ThH⁺@CB8 (2: 1) complexes with cucurbit[7,8]urils (CB7) and (CB8) in water. Unlike the case free ThH⁺ molecules, the absorption spectrum of the complexes is characterized by a hypsochromic shift of the maximum by 6 and 41 nm for ThH⁺@CB7 and 2ThH⁺@CB8, respectively. The ThH⁺@CB7 complexes exhibit fluorescence, unlike the nonfluorescing 2ThH⁺@CB8 complexes. The monomeric complexes undergo intersystem crossing to the triplet state with a lifetime of 14 μs. The dimeric complexes have a very low quantum yield of the triplet state. The triplet state of the dimeric complexes was populated by photosensitized excitation by triplet–triplet energy transfer. The lifetime of the triplet state is ≈50 μs.     

Photophysics and nonlinear absorption of peripheral-substituted zinc phthalocyanines

The photophysical properties, such as the UV-vis absorption spectra, triplet transient difference absorption spectra, triplet excited-state extinction coefficients, quantum yields of the triplet excited state, and lifetimes of the triplet excited state, of 10 novel zinc phthalocyanine derivatives with mono- or tetraperipheral substituents have been systematically investigated in DMSO solution. All these complexes exhibit a wide optical window in the visible spectral range and display long triplet excited-state lifetimes (140-240 mus). It has been found that the complexes with tetrasubstituents at the alpha-positions exhibit a bathochromic shift in their UV-vis absorption spectra, fluorescence spectra, and triplet transient difference absorption spectra and have larger triplet excited-state absorption coefficients. The nonlinear absorption of these complexes has been investigated using the Z-scan technique. It is revealed that all complexes exhibit a strong reverse saturable absorption at 532 nm for nanosecond and picosecond laser pulses. The excited-state absorption cross sections were determined through a theoretical fitting of the experimental data using a five-band model. The complexes with tetrasubstituents at the alpha-positions exhibit larger ratios of triplet excited-state absorption to ground-state absorption cross sections (sigma T/sigma g) than the other complexes. In addition, the wavelength-dependent nonlinear absorption of these complexes was studied in the range of 470-550 nm with picosecond laser pulses. All complexes exhibit reverse saturable absorption in a broad visible spectral range for picosecond laser pulses. Finally, the nonlinear transmission behavior of these complexes for nanosecond laser pulses was demonstrated at 532 nm. All complexes, and especially the four alpha-tetrasubstituted complexes, exhibit stronger reverse saturable absorption than unsubstituted zinc phthalocyanines due to the larger ratio of their excited-state absorption cross sections to their respective ground-state absorption cross sections.     

Synthesis, photophysical and photochemical properties of substituted zinc phthalocyanines

The synthesis, photophysical and photochemical properties of the 4-({3,4,5-tris-[2-(2-ethoxyethoxy)ethyloxy]benzyl}oxy) and 4-({3,4,5-tris-[2-(2-ethoxyethoxy)ethyloxy]benzyl}thio) zinc(ii) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, (1)H and (13)C NMR spectroscopy, electronic spectroscopy and mass spectra. General trends are described for photodegradation, singlet oxygen, fluorescence and triplet excited state quantum yields, and triplet state and fluorescence lifetimes of these compounds in dimethylsulfoxide (DMSO). The fluorescence of the complexes was quenched by benzoquinone (BQ). The effects of the substitution on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (6, 7 and 8) are also reported. Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The substituted Zn(II) phthalocyanines showed high triplet and singlet oxygen quantum yields. High singlet oxygen quantum yields are very important for Type II mechanism. Thus, these complexes show potential as Type II photosensitizers.     

Asymmetry in platinum acetylide complexes: confinement of the triplet exciton to the lowest energy ligand

To determine structure-optical property relationships in asymmetric platinum acetylide complexes, we synthesized the compounds trans-Pt(PBu3)2(C[triple bond]CC6H5)(C[triple bond]C-C6H4-C[triple bond]CC6H5) (PE1-2), trans-Pt(PBu3)2(C[triple bond]CC6H5)(C[triple bond]C-C6H4-C[triple bond]C-C6H4-C[triple bond]CC6H5) (PE1-3) and trans-Pt(PBu3)2(C[triple bond]C-C6H4-C[triple bond]CC6H5)(C[triple bond]C-C6H4-C[triple bond]C-C6H4-C[triple bond]CC6H5) (PE2-3) that have different ligands on either side of the platinum and compared their spectroscopic properties to the symmetrical compounds PE1, PE2 and PE3. We measured ground state absorption, fluorescence, phosphorescence and triplet state absorption spectra and performed density functional theory (DFT) calculations of frontier orbitals, lowest lying singlet states, triplet state geometries and energies. The absorption and emission spectra give evidence the singlet exciton is delocalized across the central platinum atom. The phosphorescence from the asymmetric complexes comes from the largest ligand. Time-dependent (TD) DFT calculations show the S1 state has mostly highest occupied molecular orbital (HOMO) --> lowest unoccupied molecular orbital (LUMO) character, with the LUMO delocalized over the chromophore. In the asymmetric chromophores, the LUMO resides on the larger ligand, suggesting the S1 state has interligand charge transfer character. The triplet state geometries obtained from the DFT calculations show distortion on the lowest energy ligand, whereas the other ligand has the ground state geometry. The calculated trend in the triplet state energies agrees very well with the experimental trend. Calculations of triplet state spin density also show the triplet exciton is confined to one ligand. In the asymmetric complexes the spin density is confined to the largest ligand. The results show Kasha's rule applies to these complexes, where the triplet exciton moves to the lowest energy ligand.     

Synthesis and optical behaviors of 2-(9-phenanthrenyl)-, 2-(9-anthryl)-, and 2-(1-pyrenyl)-1-alkylimidazole homologues

Eight 2-(9-phenanthrenyl)-, 2-(9-anthryl)- and 2-(1-pyrenyl)-1-alkyl-benzimidazole compounds, three 2-(9-anthryl)-1-alkylphenanthroimidazole compounds and five 4,5-diphenyl-1-alkyl-2-(9-anthryl)imidazole compounds were synthesized by alkylation reactions of the corresponding benzimidazole, phenanthroimidazole or imidazole compounds. 2-(10-Bromo-9-anthryl)-1-alkyl-benzimidazole compounds were prepared by bromination reaction of 2-(9-anthryl)-1-alkylbenzimidazole compounds. All the synthesized compounds were characterized by elemental analysis, ¹H NMR, ¹³C NMR, MS or HRMS; their absorption coefficients (), maximum absorption λ_amax, fluorescence emission maximum λ_em, Stokes shifts and fluorescence quantum yields (Φ_F) in ethyl acetate were determined; their fluorescent lifetimes (T₁ and T₂) were measured in ethyl acetate and in solid state, respectively. The crystal structure of 2-(9-anthryl)-1-n-butyl-4,5-diphenylimidazole (12a) was determined to be triclinic, space group P-1 types, using single crystal X-ray crystallography technique. The results showed that these compounds exhibited moderate fluorescence-emission abilities and higher solubility in most organic solvents than their corresponding starting materials. The relationships between the optical behaviors and structures for these compounds were discussed.     

2,2'-二苯并噁唑衍生物的合成和光性能研究

合成了16种2,2-二苯并(口恶)唑衍生物,测定了化合物的熔点、红外光谱、紫外吸收光谱、荧光发射光谱以及荧光量子产率,与1,4-二(苯并(口恶)唑1′,3′-基-2′)苯和1,4-二(苯并(口恶)唑-1′,3′-基-2′)乙烯衍生物进行了比较,讨论了它们之间光谱特性的差异.