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Triplet-Singlet Emission of d-Block Metal Complexes Characterized by Spin-Orbit Natural Transition Orbitals.

ABSTRACT: Spin-orbit natural transition orbital (SO-NTO) methodology, recently developed in our group for complete and restricted active space (CAS/RAS) wavefunction calculations, is applied to analyze triplet-to-singlet emission in transition metal complexes. The lowest-energy (longest-wavelength) spin-forbidden transition T1→S0${{{\rm T}}_{1}\to {{\rm S}}_{0}}$ is studied for for [Ir(pbt)2(acac)] and [Re(CO)4(pbt)] and the complexes [W(CO)4(bpy)] and [Mo(CO)4(bpy)]. For the latter complexes, spin-forbidden transitions from higher spin-triplet levels are additionally analyzed. SO-NTOs are compared with spin-free NTOs for the transitions under consideration. The major assignment of a spin-forbidden transition is obtained from the spin-free NTO analysis, while the source of intensity of the electronic transition is revealed by the SO-NTOs.

SUBMITTER: Zaichenko A

PROVIDER: S-EPMC11319217 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Triplet-Singlet Emission of d-Block Metal Complexes Characterized by Spin-Orbit Natural Transition Orbitals.

Zaichenko A A Autschbach J J

ChemistryOpen 20240305 8

Spin-orbit natural transition orbital (SO-NTO) methodology, recently developed in our group for complete and restricted active space (CAS/RAS) wavefunction calculations, is applied to analyze triplet-to-singlet emission in transition metal complexes. The lowest-energy (longest-wavelength) spin-forbidden transition T 1 → S 0 ${{{\rm T}}_{1}\to {{\rm S}}_{0}}$ is studied for for [Ir(pbt)2(acac)] and [Re(CO)4(pbt)] and the complexes [W(CO)4(bpy)] and [Mo(CO)4(bpy)]. For the latter complexes, s ...[more]

PMID: 38441492

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