document: In this paper, we present our experimental observations on how solvents can vary the TPA and TPF properties of fluorescent rhodamine (Rh) dyes Rh6G, RhB and Rh101. Rhodamines are well-known xanthenes dyes, which have been extensively used for many widespread applications in single-molecule detection [24], DNA-sequence determination [25], fluorescence labelling [26], etc. due to their strong fluorescence over the visible spectral region. Molecular geometries of rhodamine dyes are well-known [27,28] and indicate that all the structures are non-centrosymmetric. In general, for centrosymmetric molecules, TPA is forbidden when tuned to the transitions at one-half of the excitation frequencies. However, for non-centrosymmetric molecules due to symmetry relaxations, the single-photon absorption (SPA) peaks and TPA peaks may coincide. So we set our primary aim to find the effect of solvent polarity on the correlation of SPA and TPA peaks for all the dyes.
doc_bio_tags: O O O O O O O O O O O O O O B O B O O B I B B B B O B B O O O B O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O B O O O O O O O O O O O O O O B I B O O O O O O O O O O O O O O O O O O O B I O O O B O O B O O O O O O O O O O O O O O O O O O O O B O B O O O O B
extractive_keyphrases: centrosymmetric molecules dyes fluorescence fluorescent rhodamine rh rh101 rh6g rhb rhodamines spa symmetry relaxations tpa tpf
abstractive_keyphrases: dna-sequence determination experimental observations on how solvents can vary the tpa and tpf properties of fluorescent rhodamine (rh) dyes fluorescence labelling fluorescent rhodamine (rh) dyes non-centrosymmetric molecules rhodamine dyes single-molecule detection single-photon absorption single-photon absorption (spa) peaks tpa peaks xanthenes dyes