Low Temperature Emissive Cyclometalated Cobalt(III) Complexes

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 14, 2025

A series of CoIII complexes [Co(RImP)2][PF6], with HMeImP = 1,1'-(1,3-phenylene)bis(3-methyl-1-imidazole-2-ylidene)) and R Me, Et, iPr, nBu, is presented in this work. The influence the strong donor ligand on ground excited-state photophysical properties was investigated context different alkyl substituents at imidazole nitrogen. X-ray diffraction revealed no significant alterations structures all differences emerge from electronic structures. These were probed via cyclic voltammetry UV-vis spectroscopy, detailing ground-state properties. All are emissive 77 K a 3MC state, which exhibits lifetimes range 1-5 ns room temperature, depending substituent. Therefore, it clearly shown that even small structure have large impact details excited state landscape. observed behavior rationalized by detailed DFT analysis, shows minimum-energy crossing point to located only slightly above MC energy: Consequently, nonradiative decay temperature enabled, while path prohibited, leading low-temperature emission.

Language: Английский

Shining light on the ferrous analogue: excited state dynamics of an Fe(ii) hexa-carbene scorpionate complex

Dalton Transactions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

An Fe( ii ) complex bearing tris(carbene)borate ligands with imidazol-2-ylidene donors shows marked destabilization of metal centered states by the strongly σ-donating ligands. Yet, its high-energy 3 MLCT state is rapidly deactivated via a MC state.

Language: Английский