Cyclometallated Co(III) Complexes with Lowest-Energy Charge Transfer Excited States Accessible with Visible Light DOI
Spencer T. Burton,

Gyunhee Lee,

Curtis E. Moore

и другие.

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 10, 2025

The Co(III) complexes, cis-[Co(ppy)2(L)]PF6, where ppy = 2-phenylpyridine and L bpy (2,2'-bipyridine; 1), phen (1,10-phenanthroline; 2), DAP (1,12-diazaperylene; 3), are reported their photophysical properties were investigated to evaluate potential as sensitizers for applications that include solar energy conversion schemes photoredox catalysis. Calculations show cyclometallation in the cis-[Co(ppy)2(L)]PF6 series affords strong Co(dπ)/ppy(π) orbital interactions result a Co/ppy(π*) highest occupied molecular (HOMO) lowest unoccupied (LUMO) localized on diimine ligand, L(π*). Complexes 1-3 exhibit relatively invariant oxidation potentials, whereas reduction event is dependent identity of L, consistent with theoretical predictions. For 3 broad → L(π*) metal/ligand-to-ligand charge transfer (ML-LCT) absorption band observed CH3CN maxima at 507 nm, extending beyond 600 nm. Upon excitation 1ML-LCT transition, transient features population 3ML-LCT excited state lifetimes, τ, 3.0 ps, 4.6 42 ps 1, 2 respectively observed. irradiation 505 able reduce methyl viologen (MV2+), an electron acceptor commonly photocatalytic schemes. To our knowledge, represents first heteroleptic complex combines ligand lowest-lying metal-to-ligand states undergo photoinduced low-energy green light. As such, structural design important step toward d6 photosensitizers based earth abundant metals.

Язык: Английский

Making Mo(0) a Competitive Alternative to Ir(III) in Phosphors and Photocatalysts DOI Creative Commons
Tao Jin, Narayan Sinha,

Dorothee Wagner

и другие.

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 23, 2025

Iridium is used in commercial light-emitting devices and photocatalysis but among the rarest stable chemical elements. Therefore, replacing iridium(III) photoactive molecular complexes with abundant metals of great interest. First-row transition generally tend to yield poorer luminescence behavior, it remains difficult obtain excited states redox properties that exceed those noble-metal-based photocatalysts. Here, we overcome these challenges a nonprecious second-row metal. Tailored coordination spheres for molybdenum(0) lead photoluminescence quantum yields rival photochemical reduction reactions not normally achievable become possible. These developments open new perspectives noble lighting applications Earth-abundant advancing metal-based beyond current limits.

Язык: Английский

Процитировано

2
Copper(I) Photoredox Catalysts Bearing Tetradentate Phenanthroline-Based Ligands: Understanding the Interplay between Structure and Function DOI
Angus Olding, Lee Cameron, Le Nhan Pham

и другие.

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 3731 - 3740

Опубликована: Фев. 17, 2025

Язык: Английский

Процитировано

0
A Blessing and a Curse: Remote Ligand Functionalization Modulates 3MLCT Relaxation in Group 6 Tricarbonyl Complexes DOI
Alexander C. Fischer, Christoph Förster, Winald R. Kitzmann

и другие.

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 25, 2025

We recently reported a molecular design for carbonylpyridine molybdenum(0) complexes that unlocks long-lived luminescent and photoactive charge-transfer states. Here, we translate this strategy to chromium(0), tungsten(0) report three fully characterized tricarbonyl metal(0) featuring tripodal ligand with remote n-butyl substituent in the backbone. All show phosphorescence red near-infrared spectral region from metal-to-ligand excited Surprisingly, alkyl chain significantly affects state relaxation: lifetimes are shortened solution but extended solid by one order of magnitude compared complex methyl substituent. Temperature-dependent luminescence NMR spectroscopy combination quantum chemical calculations reveal reasons these disparate effects. The distorts metal coordination geometry. resulting structural flexibility flattens potential energy surfaces solution, which lowers barrier population distorted metal-centered states facilitates nonradiative relaxation. In state, rigidified separates neighboring molecules, reduces self-quenching. Our study sheds light on relationship between structure relaxation inform development based earth-abundant metals.

Язык: Английский

Процитировано

0
Molecular Design Principles for Photoactive Transition Metal Complexes: A Guide for “Photo-Motivated” Chemists DOI Creative Commons
Giacomo Morselli, Christian Reber, Oliver S. Wenger

и другие.

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Март 27, 2025

Luminescence and photochemistry involve electronically excited states that are inherently unstable therefore spontaneously decay to electronic ground states, in most cases by nonradiative energy release generates heat. This dissipation can occur on a time scale of 100 fs (∼10–13 s) usually needs be slowed down at least the nanosecond (∼10–9 for luminescence intermolecular occur. is challenging task with many different factors consider. An alternative emerging strategy target dissociative lead metal–ligand bond homolysis subnanosecond access synthetically useful radicals. Based thorough review recent advances field, this article aims provide concise guide obtaining luminescent photochemically coordination compounds d-block elements. We hope encourage "photo-motivated" chemists who have been reluctant apply their synthetic other knowledge photophysics photochemistry, we intend stimulate new approaches control state behavior.

Язык: Английский

Процитировано

0
Cyclometallated Co(III) Complexes with Lowest-Energy Charge Transfer Excited States Accessible with Visible Light DOI
Spencer T. Burton,

Gyunhee Lee,

Curtis E. Moore

и другие.

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Апрель 10, 2025

The Co(III) complexes, cis-[Co(ppy)2(L)]PF6, where ppy = 2-phenylpyridine and L bpy (2,2'-bipyridine; 1), phen (1,10-phenanthroline; 2), DAP (1,12-diazaperylene; 3), are reported their photophysical properties were investigated to evaluate potential as sensitizers for applications that include solar energy conversion schemes photoredox catalysis. Calculations show cyclometallation in the cis-[Co(ppy)2(L)]PF6 series affords strong Co(dπ)/ppy(π) orbital interactions result a Co/ppy(π*) highest occupied molecular (HOMO) lowest unoccupied (LUMO) localized on diimine ligand, L(π*). Complexes 1-3 exhibit relatively invariant oxidation potentials, whereas reduction event is dependent identity of L, consistent with theoretical predictions. For 3 broad → L(π*) metal/ligand-to-ligand charge transfer (ML-LCT) absorption band observed CH3CN maxima at 507 nm, extending beyond 600 nm. Upon excitation 1ML-LCT transition, transient features population 3ML-LCT excited state lifetimes, τ, 3.0 ps, 4.6 42 ps 1, 2 respectively observed. irradiation 505 able reduce methyl viologen (MV2+), an electron acceptor commonly photocatalytic schemes. To our knowledge, represents first heteroleptic complex combines ligand lowest-lying metal-to-ligand states undergo photoinduced low-energy green light. As such, structural design important step toward d6 photosensitizers based earth abundant metals.

Язык: Английский

Процитировано

0