The spectral and luminescent properties of 21-thia- and 21,23-dithia-5,10,15,20-tetraphenylporphyrin were studied in solutions at 293 K. The origin of the spectral shifts of the absorption bands upon heterosubstitution was discussed based on the Gouterman four-orbital model. Fluorescence quenching of the heteroporphyrins was shown to be due to an internal heavy-atom effect of the thiophene-ring heteroatom.

中文翻译：

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异原子在溶液中21-Thia和21,23-Dithia-5,10,15,20-四苯基卟啉的光谱发光性质形成中的作用

在293 K溶液中研究了21-噻吩和21,23-二噻吩5,10,15,20-四苯基卟啉的光谱和发光性质。讨论了基于杂取代的吸收带光谱位移的起源。古特曼四轨道模型。杂卟啉的荧光猝灭被证明是由于噻吩环杂原子的内部重原子效应。