Nickel(II) Analogues of Phosphorescent Platinum(II) Complexes with Picosecond Excited‐State Decay DOI Creative Commons
Tomohiro Ogawa, Oliver S. Wenger

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 135(46)

Published: Sept. 21, 2023

Abstract Square‐planar Ni II complexes are interesting as cheaper and more sustainable alternatives to Pt luminophores widely used in lighting photocatalysis. We investigated the excited‐state behavior of two complexes, which isostructural with luminescent complexes. The initially excited singlet metal‐to‐ligand charge transfer ( 1 MLCT) states decay metal‐centered 3 MC) within less than picosecond, followed by non‐radiative relaxation MC electronic ground state 9–21 ps. This contrasts population an emissive triplet ligand‐centered LC) upon excitation analogues. Structural distortions responsible for this discrepant lead dark far lower energy LC compounds. Our findings suggest that if these structural could be restricted rigid coordination environments stronger ligand fields, four‐coordinate decelerated such or MLCT become accessible. These insights relevant make fit photophysical photochemical applications relied on until now.

Language: Английский

Nickel(II) Analogues of Phosphorescent Platinum(II) Complexes with Picosecond Excited‐State Decay DOI Creative Commons
Tomohiro Ogawa, Oliver S. Wenger

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(46)

Published: Sept. 21, 2023

Square-planar NiII complexes are interesting as cheaper and more sustainable alternatives to PtII luminophores widely used in lighting photocatalysis. We investigated the excited-state behavior of two complexes, which isostructural with luminescent complexes. The initially excited singlet metal-to-ligand charge transfer (1 MLCT) states decay metal-centered (3 MC) within less than 1 picosecond, followed by non-radiative relaxation 3 MC electronic ground state 9-21 ps. This contrasts population an emissive triplet ligand-centered LC) upon excitation analogues. Structural distortions responsible for this discrepant lead dark far lower energy LC compounds. Our findings suggest that if these structural could be restricted rigid coordination environments stronger ligand fields, four-coordinate decelerated such or MLCT become accessible. These insights relevant make fit photophysical photochemical applications relied on until now.

Language: Английский

Citations

25
Carbon Dioxide Electroreduction and Formic Acid Oxidation by Formal Nickel(I) Complexes of Di‐isopropylphenyl Bis‐iminoacenaphthene DOI
Vera V. Khrizanforova, Robert R. Fayzullin, Sergey V. Kartashov

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(24)

Published: Feb. 21, 2024

Abstract Processing CO 2 into value–added chemicals and fuels stands as one of the most crucial tasks in addressing global challenge greenhouse effect. In this study, we focused on complex (dpp–bian)NiBr (where dpp–bian is di‐isopropylphenyl bis‐iminoacenaphthene) a precatalyst for electrochemical reduction CH 4 sole product. Cyclic voltammetry results indicate that realization catalytically effective pattern requires three–electron . The chemically reduced complexes [K(THF) 6 ] + [(dpp–bian)Ni(COD)] − [(dpp–bian) Ni] were synthesized structurally characterized. Analyzing data from electron paramagnetic resonance study solutions, along with quantum–chemical calculations, reveals spin density predominantly localized at their metal centers. superposition trajectory maps gradient vector field electrostatic force per electron, well atomic charges, discloses that, within first coordination sphere, interatomic charge transfer occurs atom to ligand atoms anions can thus be formally described by general formulae (dpp–bian) 2− Ni (COD) It was also shown nickel oxidized formic acid; resulting reaction, two–electron two–proton addition product dpp–bian–2H formed.

Language: Английский

Citations

7
Nickel(II) Analogues of Phosphorescent Platinum(II) Complexes with Picosecond Excited‐State Decay DOI Creative Commons
Tomohiro Ogawa, Oliver S. Wenger

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 135(46)

Published: Sept. 21, 2023

Abstract Square‐planar Ni II complexes are interesting as cheaper and more sustainable alternatives to Pt luminophores widely used in lighting photocatalysis. We investigated the excited‐state behavior of two complexes, which isostructural with luminescent complexes. The initially excited singlet metal‐to‐ligand charge transfer ( 1 MLCT) states decay metal‐centered 3 MC) within less than picosecond, followed by non‐radiative relaxation MC electronic ground state 9–21 ps. This contrasts population an emissive triplet ligand‐centered LC) upon excitation analogues. Structural distortions responsible for this discrepant lead dark far lower energy LC compounds. Our findings suggest that if these structural could be restricted rigid coordination environments stronger ligand fields, four‐coordinate decelerated such or MLCT become accessible. These insights relevant make fit photophysical photochemical applications relied on until now.

Language: Английский

Citations

0