Effect of hydration on the luminescence properties of 2,2-difluoro-4-methylnaphto[2,1-e]-1,3,2-dioxaborine. Quantum chemical modeling and experiment

Abstract

The effect of hydration on the spectral luminescence properties of solutions of 2,2 difluoro 4 methylnaphto[2,1 e] 1,3,2 dioxaborine in organic solvents is studied. Quenching of lumi nescence and color changes of the solutions associated with hydration of luminophore molecules were observed. Quantum chemical modeling of the structure of the hydrate complex is carried out.Key words: quantum chemical calculations, density functional theory, difluoroboron β diketonates, luminescence, hydrogen bond. Fluorescent dyes immobilized in polymeric mat rices and capable of "on" and "off" switching their luminescence are promising systems for the design of reversible, reusable luminescence on off optical fiber sensors. 1-3Difluoroboron β diketonates exhibit bright fluore scence in the crystalline state 4 and in solutions, 5-7 thus being promising compounds for use as luminescent dyes for polymers. 8,9 In the present work, we report for the first time on reversible on off luminescence switching of solutions of 2,2 difluoro 4 methylnaphtho[2,1 e] [1,3,2]dioxa borine (1) in organic solvents upon addition of water.There is a number of on off luminescence switching mechanisms, e.g., (i) inversion of nπ-ππ states due to involvement of n electrons of heteroatoms in the forma

Optical Signatures of OBO Fluorophores: A Theoretical Analysis

“…In fact, fluoroborate fluorophores can be classified into major categories depending on their atomic sequence: NBN, NBO, or OBO-bidentate ligands have indeed been proposed. The latter compounds, which are the focus of this work, present several molecular architectures (see Scheme ). − The compounds shown in Scheme have absorption and emission wavelengths spanning the 350–550 nm window [see Table S-I in the Supporting Information (SI)]. To effectively predict the optical signatures of OBO dyes, theoretical chemistry can be a handy tool.…”