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Giant Multi-Photon Absorption by Heptazine Organometalation.

ABSTRACT: Multi-photon absorption (MPA) is of increasing interest for applications in technologically important "windows" of the electromagnetic spectrum (near-infrared III, NIR-III, 1550-1870 nm; and the new 2080-2340 nm region); however, few molecules exist that display strong MPA at these long wavelengths. We herein report the syntheses of the first 2,5,8-s-heptazine-cored organometallic complexes, together with organic analogues. The complexes exhibit outstanding 3PA cross-sections in the NIR-III and exceptional 4PA cross-sections in the new 2080-2340 nm window. We demonstrate that replacing organic donor groups by organometallic units results in an order of magnitude increase in 3PA, the "switching on" of 4PA, and a dramatic improvement in photo-stability. Our results highlight the impressive outcomes possible with an "organometalation" approach to NLO materials design.

SUBMITTER: Zhang L

PROVIDER: S-EPMC9546223 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Giant Multi-Photon Absorption by Heptazine Organometalation.

Zhang Ling L Morshedi Mahbod M Kodikara Mahesh S MS Humphrey Mark G MG

Angewandte Chemie (International ed. in English) 20220719 37

Multi-photon absorption (MPA) is of increasing interest for applications in technologically important "windows" of the electromagnetic spectrum (near-infrared III, NIR-III, 1550-1870 nm; and the new 2080-2340 nm region); however, few molecules exist that display strong MPA at these long wavelengths. We herein report the syntheses of the first 2,5,8-s-heptazine-cored organometallic complexes, together with organic analogues. The complexes exhibit outstanding 3PA cross-sections in the NIR-III and ...[more]

PMID: 35778270

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