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NIR-Emissive Chromium(0), Molybdenum(0), and Tungsten(0) Complexes in the Solid State at Room Temperature.

ABSTRACT: The development of NIR emitters based on earth-abundant elements is an important goal in contemporary science. We present here Cr(0), Mo(0), and W(0) carbonyl complexes with a pyridyl-mesoionic carbene (MIC) based ligand. A detailed photophysical investigation shows that all the complexes exhibit dual emissions in the VIS and in the NIR region. The emissive excited states are assigned to two distinct triplet states by time-resolved emission and step-scan FTIR spectroscopy at variable temperature, supported by density functional theory. In particular, the NIR emissive triplet state exhibits unprecedented lifetimes of up to 600±10 ns and quantum yields reaching 1.7 ⋅ 10^-4 at room temperature. These are the first examples of Cr(0), Mo(0) and W(0) complexes that emit in the NIR II region.

SUBMITTER: Boden P

PROVIDER: S-EPMC8519045 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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NIR-Emissive Chromium(0), Molybdenum(0), and Tungsten(0) Complexes in the Solid State at Room Temperature.

Boden Pit P Di Martino-Fumo Patrick P Bens Tobias T Steiger Sophie S Albold Uta U Niedner-Schatteburg Gereon G Gerhards Markus M Sarkar Biprajit B

Chemistry (Weinheim an der Bergstrasse, Germany) 20210804 51

The development of NIR emitters based on earth-abundant elements is an important goal in contemporary science. We present here Cr(0), Mo(0), and W(0) carbonyl complexes with a pyridyl-mesoionic carbene (MIC) based ligand. A detailed photophysical investigation shows that all the complexes exhibit dual emissions in the VIS and in the NIR region. The emissive excited states are assigned to two distinct triplet states by time-resolved emission and step-scan FTIR spectroscopy at variable temperature ...[more]

PMID: 34237175

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