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1.
利用2-苯基吡啶及其衍生物为主配体、四苯基膦酰亚胺为辅助配体合成了3个铱配合物Ir(ppy)2tpip(Hppy:2-苯基吡啶,Htpip:四苯基膦酰亚胺)、Ir(npy)2tpip(Hnpy:2-(1-萘基)吡啶)和Ir(pnpy)2tpip(Hpnpy:2-(9-菲基)吡啶)。它们的结构通过1HNMR和MALDI-TOF质谱进行了表征,其中配合物Ir(ppy)2tpip还进一步通过晶体结构分析验证。主配体从苯环到萘环和菲环的改变增加了配合物的π共轭,减小了能级差,导致了3种配合物的磷光发射光谱从516nm红移到600和633nm(从绿光到红光),发光量子效率也从0.36增加到0.51和0.53。从量化计算的结果可以看出,这种共轭效应增加了主配体的电子密度,提高了配合物的LUMO能级。配合物结构和发射性质之间的关系规律为设计不同发光颜色的铱配合物提供了思路。  相似文献   

2.
刘恒  罗彩芹 《化学通报》2014,77(4):382-384
利用环金属配体2-苯基吡啶(ppy)和辅助配体2,2'-联吡啶-3,3’-二羧酸(H2dcbpy)合成了一个铱配合物[Ir(ppy)2(Hdcbpy)],并且测定了其晶体结构。通过对配合物的紫外可见吸收光谱和发光光谱的研究表明,其常温发射位于620nm处,初步推测该磷光发射可能来自由金属到环金属配体和辅助配体的电荷转移(MLCT)跃迁。  相似文献   

3.
利用环金属配体2-苯基吡啶(ppy)和辅助配体2,2'-联吡啶-3,3’-二羧酸(H2dcbpy)合成了一个铱配合物[Ir(ppy)2(Hdcbpy)],并且测定了其晶体结构。通过对配合物的紫外可见吸收光谱和发光光谱的研究表明,其常温发射位于620nm处,初步推测该磷光发射可能来自由金属到环金属配体和辅助配体的电荷转移(MLCT)跃迁。  相似文献   

4.
采用2-(4-三氟甲基苯基)吡啶(tfmppy)为主配体,分别以四(4-氟苯基)苯基膦酰亚胺(F-tpip)、四(4-甲氧基苯基)膦酰亚胺(MeO-tpip)和四(1-萘基)膦酰亚胺(tnin)为辅助配体合成了3个铱配合物((tfmppy)_2Ir(F-tpip)、(tfmppy)_2Ir(MeO-tpip)和(tfmppy)_2Ir(tnin))。其结构通过核磁氢谱、质谱、元素分析和单晶结构测定进行了验证。配合物(tfmppy)_2Ir(F-tpip)和(tfmppy)_2Ir(MeO-tpip)属于三方晶系P1空间群,配合物(tfmppy)_2Ir(tnin)属于三斜晶系R3c空间群。3个配合物都是绿光材料,具有类似的发光颜色和发光效率((tfmppy)_2Ir(F-tpip):λ_(em)=526 nm,Φ=0.52;(tfmppy)_2Ir(MeO-tpip):λ_(em)=523 nm,Φ=0.44;(tfmppy)_2Ir(tnin):λ_(em)=522 nm,Φ=0.48)。3个配合物的循环伏安曲线都显示出了良好的氧化还原性质。(tfmppy)_2Ir(F-tpip)、(tfmppy)_2Ir(MeO-tpip)和(tfmppy)_2Ir(tnin)的HOMO能级分别为-5.67、-6.08和-5.69 eV,其LUMO能级分别为-3.29、-3.61和-3.22 eV。  相似文献   

5.
合成了一系列含有吡咯亚胺基为辅助配体的2-苯基吡啶铱配合物[(ppy)2Ir(N^N)] (ppy=2-苯基吡啶), 通过1H NMR, MS, HRMS和元素分析对配合物结构进行了表征, 并研究了合成配合物的反应条件、紫外吸收光谱、光致发光光谱及铱配合物荧光量子产率. 结果表明, 在无水乙酸钠、二氯甲烷溶液中, 室温反应12 h可获得较高的产率. 通过改变吡咯亚胺类配体中的取代基, 该类配合物在507~606 nm之间具有不同的发光波长, 实现了从绿光到红光的转变. 所有的铱配合物在二氯甲烷溶液(空气中)表现出较高的量子效率(0.25~0.95).  相似文献   

6.
合成了一系列含有吡咯亚胺基为辅助配体的2-苯基吡啶铱配合物[(ppy)zIr(NAN)](ppy=2-苯基吡啶),通过1H NMR,MS,HRMS和元素分析对配合物结构进行了表征,并研究了合成配合物的反应条件、紫外吸收光谱、光致发光光谱及铱配合物荧光量子产率.结果表明,在无水乙酸钠、二氯甲烷溶液中,室温反应12 h可获得较高的产率.通过改变吡咯亚胺类配体中的取代基,该类配合物在507~606 nm之间具有不同的发光波长,实现了从绿光到红光的转变.所有的铱配合物在二氯甲烷溶液(空气中)表现出较高的量子效率(0.25~0.95).  相似文献   

7.
由于具有P=O键,二(二苯基膦酰)胺(tetraphenylimidodiphosphinate acid,Htpip)作为辅助配体引入Ir(III)配合物中,可以提高配合物的电子迁移率和器件的效率。采用氟取代的2-(4-氟苯基)吡啶(F4-ppy)为主配体、以Htpip和三氟甲基取代的Htfmtpip为辅助配体合成了2个铱配合物Ir(F4-ppy)2(tpip)和Ir(F4-ppy)2(tfmtpip)。晶体结构中Ir原子的配位几何构型均为八面体构型,Ir(F4-ppy)2(tpip)属于正交晶系Pbca空间群,而Ir(F4-ppy)2(tfmtpip)属于单斜晶系P21/c空间群。配合物都具有较好的热稳定性,Ir(F4-ppy)2(tpip)和Ir(F4-ppy)2(tfmtpip)的初始分解温度分别为385和395℃。配合物Ir(F4-ppy)2(tfmtpip)的氧化和还原峰较配合物Ir(F4-ppy)2(tpip)分别向正电压移动了大约0.134和0.12 V,相应的HOMO和LUMO能级分别降低了0.14和0.43 eV。在室温、1×10-5mol·L-1的CH2Cl2溶液中Ir(F4-ppy)2(tpip)和Ir(F4-ppy)2(tfmtpip)的最大磷光发射峰分别位于492和495 nm,量子效率分别为9.2%和16.4%。结果表明在辅助配体上引入4个三氟甲基后不仅可以提高配合物的热稳定性和电化学稳定性,并且可以调控配合物的HOMO/LUMO能级和发光效率。  相似文献   

8.
以二(二苯基磷酰)胺(Htpip)作为辅助配体,与主配体2-(2,4-二氟苯基)异喹啉和2-(4-三氟甲基苯基)异喹啉合成了红光铱磷光配合物Ir(dfpiq)2tpip和Ir(tfmpiq)2tpip并得到了晶体结构。在CH2Cl2中发射光谱主要是MLCT发射,峰位置分别为622和600 nm,量子效率分别为15%和17%,而HOMO/LUMO能级分别是-4.80/-2.58和-4.73/-2.57 eV。在1150~1300(V·cm-1)1/2电场范围,Ir(dfpiq)2tpip的电子迁移率为6.61~8.49×10-6cm2·V-1·s-1,Ir(tfmpiq)2tpip的电子迁移率为6.08~6.61×10-6cm2·V-1·s-1。ITO/TAPC(60 nm)/Ir-complex(15wt%):CBP(50 nm)/TPBi(60 nm)/LiF(1 nm)/Al(100 nm)中基于Ir(dfpiq)2tpip的器件最大安培效率和功率效率分别为4.71 cd·A-1和1.82 lm·W-1,12.0 V时达到的最大亮度为18 195 cd·m-2。基于Ir(tfmpiq)2tpip的器件最大安培效率和功率效率分别为3.47 cd·A-1和1.51 lm·W-1,12.4 V时达到的最大亮度为14 676 cd·m-2。  相似文献   

9.
利用环金属配体2-(4',6'-二氟苯基)吡啶(dfppy)和副配体2,2'-联嘧啶(bpm)合成了一个铱配合物[Ir(dfppy)z(bpm)]Cl,通过1H NMR,质谱,元素分析及红外光谱对其进行了表征,并且测定了其晶体结构.同时利用得到的中间配合物[Ir(dfppy):(bpm)] [Ir(dfppy)2(Cl)2]n晶体结构讨论了配合物形成过程.对配合物[Ir(dfppy)2(bpm)]Cl的紫外可见吸收光谱和发光光谱的研究表明,其常温发射位于609 nm处,初步推测该磷光发射可能来自金属到配体的电荷转移(MLCT)跃迁和配体自身,π→π*跃迁(LC)的混合.  相似文献   

10.
利用环金属化配体2-(2’,4’-二氟苯基)-4-甲基吡啶(dfpmpy)和辅助配体5-(三氟甲基)-2-吡啶甲酸(tfmpic)合成了一个铱配合物[Ir(dfpmpy)2(tfmpic)],并测定了该配合物的光物理和电化学性质。在乙腈溶液中,配合物发射黄色磷光,其最大波长位于554 nm,理论计算表明其磷光来自于金属和环金属化配体到辅助配体或配体间的电荷转移跃迁(3MLCT或3LLCT)。  相似文献   

11.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

12.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

13.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

14.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

15.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

16.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.  相似文献   

18.
19.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

20.
潘素娟  全灿  周俊波 《化学通报》2014,77(12):1165-1170
测量不确定度是表征合理地赋予被测量之值的分散性的参数。本文针对化学计量不确定度评定基础模型仅适用于线性模型、概率分布为正态分布或缩放位移t分布等局限,介绍了近年来不确定度评定的研究热点:蒙特卡罗方法(Monte Carlo Method,MCM),不确定度评定的来源、评定概念、评估方法及其发展过程,扩大了测量不确定度评定与表示的适用范围。  相似文献   

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