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Title: A molecular boron cluster-based chromophore with dual emission
Bromination of the luminescent borane, anti -B 18 H 22 , via electrophilic substitution using AlCl 3 and Br 2 , yields the monosubstituted derivative 4-Br- anti -B 18 H 21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br- anti -B 18 H 21 possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Φ total = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe.  more » « less
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Date Published:
Journal Name:
Dalton Transactions
Page Range / eLocation ID:
16245 to 16251
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

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