TY - JOUR
T1 - Molecular structure perspective on Temperature-Sensitive properties of rhodamine aqueous solutions
AU - Liu, Ting
AU - Huang, Jianwei
AU - Ding, He
AU - Zhan, Chengsen
AU - Wang, Shouyu
N1 - Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/7/5
Y1 - 2022/7/5
N2 - As one of the most commonly used organic fluorescent dyes, recently rhodamines have been successfully employed in temperature sensing. However, few works have been reported on their temperature-sensitive properties, which inevitably limiting their further applications. In order to solve such problem, we investigated temperature-sensitive properties of rhodamine 110, 123, 19, 6G, B and 3B focusing on their fluorescence emission spectra; and analyzed them in the molecular structure perspective. It is demonstrated that the fluorescence emission intensities of all studied rhodamines decreased with higher temperature, which inevitably enhances the probability of collisions among molecules, thus definitely leads to energy loss in fluorescence emission. While these rhodamines still have various temperature sensitivities mainly due to the substitutes: the substitute on the benzene carboxylate has little effect; the amino substituents of the three-ring xanthene enhance the temperature sensitivity due to their rotation weakening the rigidity of the three-ring xanthene; and the methyl substituents on the three-ring xanthene reduce the temperature sensitivity by enhancing the rigidity and stability of the three-ring xanthene as well as hindering the rotation of ethylamino. These findings can also be extended to other organic fluorescent dyes proved by coumarins comparable to rhodamines. The results provided by this work can be useful reference and guidance to further develop organic fluorescent dyes especially for temperature sensing.
AB - As one of the most commonly used organic fluorescent dyes, recently rhodamines have been successfully employed in temperature sensing. However, few works have been reported on their temperature-sensitive properties, which inevitably limiting their further applications. In order to solve such problem, we investigated temperature-sensitive properties of rhodamine 110, 123, 19, 6G, B and 3B focusing on their fluorescence emission spectra; and analyzed them in the molecular structure perspective. It is demonstrated that the fluorescence emission intensities of all studied rhodamines decreased with higher temperature, which inevitably enhances the probability of collisions among molecules, thus definitely leads to energy loss in fluorescence emission. While these rhodamines still have various temperature sensitivities mainly due to the substitutes: the substitute on the benzene carboxylate has little effect; the amino substituents of the three-ring xanthene enhance the temperature sensitivity due to their rotation weakening the rigidity of the three-ring xanthene; and the methyl substituents on the three-ring xanthene reduce the temperature sensitivity by enhancing the rigidity and stability of the three-ring xanthene as well as hindering the rotation of ethylamino. These findings can also be extended to other organic fluorescent dyes proved by coumarins comparable to rhodamines. The results provided by this work can be useful reference and guidance to further develop organic fluorescent dyes especially for temperature sensing.
KW - Fluorescence emission spectra
KW - Light absorption spectra
KW - Molecular structure
KW - Rhodamines
KW - Temperature-sensitive properties
UR - http://www.scopus.com/inward/record.url?scp=85126551267&partnerID=8YFLogxK
U2 - 10.1016/j.saa.2022.121166
DO - 10.1016/j.saa.2022.121166
M3 - Article
C2 - 35313177
AN - SCOPUS:85126551267
SN - 1386-1425
VL - 275
JO - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
JF - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
M1 - 121166
ER -