This study deals with the effects of different sets of binary solvents on the Two-Photon Induced Fluorescence (TPIF), a non-linear process, of the Rhodamine-6G (Rh6G) dye, which is a well-known xanthene dye. This work examines the importance of inter-molecular interactions, which results in the modulation of the TPIF of the Rh6G. In this work, we have investigated three binary solvent mixtures representing varying polarity and intermolecular interactions. Specific solvent mixtures used are methanol-water, methanol-dimethyl formamide, and methanol-chloroform. Since the solvent polarity across these binary solvents differs, there are significant intermolecular interactions in the binary mixture solvents, which modulate the two-photon process of Rh6G when irradiated with high-intensity laser light at 780 nm. In our studies, we find that Rh6G in the MeOH-H₂O binary solvent has maximum red-shift and minimum intensity as compared to other pairs of binary liquids when the volume fraction of methanol decreases due to more extensive hydrogen bonding between the two components. Additionally, at 1:1 ratio of binary mixtures, Rh6G is found to have the highest TPEACS value for methanol-chloroform binary solvent and reason for that is related to the formation of weak H-bond networks between proton donor chloroform and proton acceptor methanol.

中文翻译：

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罗丹明 6G 染料在不同二元溶剂组中的双光子诱导荧光研究。

本研究探讨了不同组的二元溶剂对罗丹明 6G (Rh6G) 染料（一种众所周知的呫吨染料）双光子诱导荧光 (TPIF) 的非线性过程的影响。这项工作检查了分子间相互作用的重要性，这导致了 Rh6G 的 TPIF 的调制。在这项工作中，我们研究了代表不同极性和分子间相互作用的三种二元溶剂混合物。使用的特定溶剂混合物是甲醇-水、甲醇-二甲基甲酰胺和甲醇-氯仿。由于这些二元溶剂的溶剂极性不同，二元混合溶剂中存在显着的分子间相互作用，当用 780 nm 的高强度激光照射时，它会调节 Rh6G 的双光子过程。在我们的研究中，当甲醇的体积分数由于两种组分之间更广泛的氢键而降低时，与其他二元液体对相比，_{2 O 二元溶剂具有最大红移和最小强度。}此外，在二元混合物的比例为 1:1 时，发现 Rh6G 在甲醇-氯仿二元溶剂中具有最高的 TPEACS 值，其原因与质子供体氯仿和质子受体甲醇之间弱氢键网络的形成有关。