New Fuchsine molecules in solution and thin-film show different excited-state relaxation pathways due to the twisting of phenyl rings after photoexcitation. Transient absorption measurement reveals dominant conical intersection mediated nonradiative channel in solution whereas triplet assisted radiative channel is observed for thin-films. Photoluminescence measurements of thin-films at cryogenic temperatures reflect enhancement of radiative recombination due to the restriction of twisting in the molecules.

中文翻译：

---

新型品红-三苯甲烷衍生物染料的超快激发态弛豫动力学

由于光激发后苯环的扭曲，溶液和薄膜中的新品红分子显示出不同的激发态弛豫途径。瞬态吸收测量揭示了溶液中占主导地位的锥形交叉介导的非辐射通道，而在薄膜中观察到三重态辅助辐射通道。由于分子扭曲的限制，低温下薄膜的光致发光测量反映了辐射复合的增强。