Evans Rachel C, Douglas Peter, Winscom Christopher J
Department of Chemistry, University of Wales Swansea, Singleton Park, Swansea, SA2 8PP, UK.
J Fluoresc. 2009 Jan;19(1):169-77. doi: 10.1007/s10895-008-0399-x. Epub 2008 Aug 6.
The photophysics and cyclic voltammetry of two novel phosphorescent thiones, 2,2-dimethyl-indan-1-one-3-thione (DMIKT) and 2,2-dimethyl-indan-1,3-dithione (DMIDT), and three known phosphorescent thiones, 4H-pyran-4-thione (PT), 4H-1-benzopyran-4-thione (BPT) and 2,2-dimethylindan-1-thione (DMIT), have been characterised and compared. The phosphorescence emission of DMIT, DMIKT and DMIDT extends from the red into the near-IR spectral region. The additional carbonyl or thione group of DMIKT and DMIDT causes a significant shift in the emission maxima to 680 nm compared to that of DMIT, at 637 nm, in perfluorinated hydrocarbons. In acetonitrile the emission maxima of DMIKT and DMIDT are at 696 and 706 nm, respectively, and the spectra show vibronic bands which extend out beyond 850 nm. There is a significant reduction in triplet lifetime along this series (from 44 (+/-2) micros (DMIT) to 10 ((+/-0.8) micros (DMIKT) in perfluorinated solvents, and 8.6 (+/-0.5) (DMIT), 1.3 (+/-0.5) (DMIKT) and 0.35 (+/-0.07) micros (DMIDT) in acetonitrile), as well as a reduction in the rate constant for ground-state quenching of the triplet, (from 9.8 ((+/-0.9) to 3.5 ((+/-0.6) and 1.3 ((+/-0.2)x10(9) mol(-1) dm3 s(-1) for the same compounds). The addition of the C=O or C=S groups also causes a decrease in phosphorescence quantum yield with the highest emission quantum yield obtained for DMIT (PhiP=0.149 (+/-0.015)). Electrochemical studies show that while PT and BPT exhibit irreversible redox behaviour, DMIT, DMIKT and DMIDT all show at least one reversible reduction wave attributed to a one-electron process centred on the C=S moiety. The suitability of these lumophores for use in OLEDs is discussed.
对两种新型磷光硫酮，即2,2 - 二甲基茚满 - 1 - 酮 - 3 - 硫酮（DMIKT）和2,2 - 二甲基茚满 - 1,3 - 二硫酮（DMIDT），以及三种已知的磷光硫酮，即4H - 吡喃 - 4 - 硫酮（PT）、4H - 1 - 苯并吡喃 - 4 - 硫酮（BPT）和2,2 - 二甲基茚满 - 1 - 硫酮（DMIT）的光物理性质和循环伏安法进行了表征和比较。DMIT、DMIKT和DMIDT的磷光发射从红色延伸至近红外光谱区域。与DMIT相比，DMIKT和DMIDT额外的羰基或硫酮基团使发射最大值显著位移至680 nm，而DMIT在全氟烃中的发射最大值为637 nm。在乙腈中，DMIKT和DMIDT的发射最大值分别为696和706 nm，并且光谱显示出延伸至850 nm以外的振动带。沿着这个系列，三重态寿命显著降低（在全氟溶剂中从44（±2）微秒（DMIT）降至10（±0.8）微秒（DMIKT），在乙腈中为8.6（±0.5）（DMIT）、1.3（±0.5）（DMIKT）和0.35（±0.07）微秒（DMIDT）），同时三重态基态猝灭的速率常数也降低（对于相同的化合物，从9.8（±0.9）降至3.5（±0.6）和1.3（±0.2）×10⁹ mol⁻¹ dm³ s⁻¹）。C = O或C = S基团的添加也导致磷光量子产率降低，DMIT获得最高的发射量子产率（ΦP = 0.149（±0.015））。电化学研究表明，虽然PT和BPT表现出不可逆的氧化还原行为，但DMIT、DMIKT和DMIDT都至少显示出一个可逆的还原波，这归因于以C = S部分为中心的单电子过程。讨论了这些发光体用于有机发光二极管（OLED）的适用性。
