Coexistence of photoluminescence from two intrachain states in polythiophene films
Coexistence of photoluminescence from two intrachain states in polythiophene films
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聚噻吩薄膜中两种链内态光致发光的共存
DOI：
10.1103/physrevb.67.205214
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发表时间：
2003
影响因子：
3.7
通讯作者：
K. Sanui
中科院分区：
文献类型：
--
作者：
Takashi Kobayashi;J. Hamazaki;H. Kunugita;K. Ema;T. Endo;M. Rikukawa;K. Sanui
比较了聚噻吩（PT）衍生物高有序和无序薄膜的时间分辨光致发光（PL）测量结果。虽然$\ensuremath{\pi}$电子的离域长度和链间相互作用的强度在两种薄膜之间有很大的不同，但通常观察到双指数衰减和光谱形状的变化，从一个大的0-0跃迁到一个大的0-1跃迁。因此，我们得出结论，PT的PL光谱由具有不同光谱形状和不同寿命的两个组分组成，这些组分源于电子-声子相互作用耦合的链内奇宇称态和偶宇称态。该模型解释了有序薄膜的荧光产率大大降低以及时间分辨PL测量。
Time-resolved photoluminescence (PL) measurements on highly ordered and disordered films of a polythiophene (PT) derivative were compared. Although delocalization lengths of $\ensuremath{\pi}$ electrons and the strengths of interchain interaction are quite different between the two films, a biexponential decay and a change in spectral shape, from one with a large 0-0 transition to one with a large 0-1 transition, were commonly observed. Therefore, we conclude that PL spectra of PT consist of two components having different spectral shapes and different lifetimes, and that these components originate from intrachain odd- and even-parity states that are coupled by electron-phonon interaction. This model explains the greatly reduced fluorescence yield for the ordered film as well as the time-resolved PL measurements.