A Bichromophoric Approach to Induce Luminescence - A Blend of Experimental and Theoretical Studies

Rahat Gupta; Anshul Negi; Amlan K Pal

doi:10.1002/asia.202400270

A Bichromophoric Approach to Induce Luminescence - A Blend of Experimental and Theoretical Studies

Chem Asian J. 2024 May 14:e202400270. doi: 10.1002/asia.202400270. Online ahead of print.

Authors

Rahat Gupta¹, Anshul Negi¹, Amlan K Pal²

Affiliations

¹ Indian Institute of Technology Jammu, Chemistry, INDIA.
² Indian Institute of Technology Jammu, Chemistry, Jagti, NH-44, Nagrota, 181221, Jammu, INDIA.

PMID: 38742860
DOI: 10.1002/asia.202400270

Abstract

Two homoleptic terpyridyl complexes of Ru(II), 1 and Fe(II), 2 were synthesized using a ligand L1 that contained a phenyl spacer between an anthracenyl (An) and a terpyridyl (tpy) moiety. An equilibrated-bichromophoric strategy was adopted to induce photoluminescence in 1 and 2. A glimpse into the excited state photophysical properties of 1 and 2 revealed that 1 exhibited NIR emission at ~ 700 nm with an excited state lifetime components of 1.33 and 6.52 ns. On the other hand, 2 was found to be non-luminescent. The origin of emission in case of 1 was attributed to the effect of phenyl spacer which rendered the 3An state to be nearly isoenergetic to the emissive 3MLCT state of 1 facilitating 3MLCT-3An equilibrium. This fact was supported by experimental (photocurrent generation) and theoretical (potential energy diagram) evidences.

Keywords: bichromophoric approach; photocurrent; potential energy diagram; spectralelectrochemistry; terpyridine complexes.