doi:10.1021/acs.inorgchem.5c03511engJiménez, RaquelCrespo, OlgaGimeno, M. ConcepciónDiphosphane-Mediated Control of the Emissive Properties in [Cu(NHC)(P^P)] ⁺ Complexes: TADF vs PhosphorescenceART-2025-146289The influence of both the skeleton and substituents of the diphosphane in the photophysical properties of [Cu(NHC)(P^P)]PF6 TADF-phosphorescent emitters is investigated [NHC = Bz-Im-2-XPy (X = H, Cl)]. The study reveals that optimization of the diphosphane structure can boost quantum yields to as high as 85% using carbenes with simple structural frameworks or substituent wings. Remarkably, the diphosphane skeleton emerges as the most influential factor for controlling the quantum yield (Φ). None of the ΔE(S1-T1) energy gap, steric factors (buried volume percentage), or T1 energy alone seem to govern the observed Φ. These insights reveal new avenues for achieving high-performance TADF emitters through ligand engineering.2025http://zaguan.unizar.es/record/16412910.1021/acs.inorgchem.5c03511http://zaguan.unizar.es/record/164129oai:zaguan.unizar.es:164129info:eu-repo/grantAgreement/ES/DGA-FSE/A07_23Rinfo:eu-repo/grantAgreement/ES/MICINN AEI/PID2022-136861NB-I00info:eu-repo/grantAgreement/ES/MICINN/TED2021-130447B-I00Inorganic Chemistry 64, 43 (2025), 21541-21550 [10 pp.]byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess