Charge Shift/Recombination and Triplet Formation in a Molecular Dyad based on a Borondipyrromethene (Bodipy) and an Expanded Acridinium Cation. Issue 3 (5th January 2018)

• Record Type: Journal Article
• Authors: He, Xiaoyan; Benniston, Andrew C.; Lemmetyinen, Helge; Tkachenko, Nikolai V.
• Is Part Of: ChemPhotoChem. Volume 2:Issue 3(2018)
• Page Start: 277
• Page End: 282
• Publication Date: 2018-01-05
• Subjects: acridinium -- bodipy -- charge recombination -- charge separation -- excited states; Photochemistry -- Periodicals; Periodicals; Electronic journals; 541.35
• DOI: 10.1002/cptc.201700184
• Languages: English
• ISSNs: 2367-0932

Abstract

Abstract: A molecular monocationic dyad comprising a borondipyrromethene (Bodipy) and an expanded planar acridinium cation was prepared. The dyad, when excited in solution by an ultrashort laser pulse, generates a charge‐shift state, where a positive charge is transferred to the Bodipy from the acridinium subunit. The process takes less than 1 ps in MeCN and around 8 ps in 1, 2‐dichloroethane. The charge‐shift state collapses, in part, back to the ground state but it also leads to partial triplet formation; the discrimination between rates for the forward and reverse processes is circa 7. Abstract : Walk the line : Coupling of a borondipyrromethene (Bodipy) to an electron‐accepting expanded acridinium cation produced a linear dyad which strongly absorbs to around λ =550 nm. Excitation of either chromophore results in an ultrafast shift of positive charge to the Bodipy and is accompanied by restoration of the ground state and localised triplet formation.