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Abstract Two-photon excited near-infrared fluorescence materials have garnered considerable attention because of their superior optical penetration, higher spatial resolution, and lower optical scattering compared with other optical materials. Herein, a convenient and efficient supramolecular approach is used to synthesize a two-photon excited near-infrared emissive co-crystalline material. A naphthalenediimide-based triangular macrocycle and coronene form selectively two co-crystals. The triangle-shaped co-crystal emits deep-red fluorescence, while the quadrangle-shaped co-crystal displays deep-red and near-infrared emission centered on 668 nm, which represents a 162 nm red-shift compared with its precursors. Benefiting from intermolecular charge transfer interactions, the two co-crystals possess higher calculated two-photon absorption cross-sections than those of their individual constituents. Their two-photon absorption bands reach into the NIR-II region of the electromagnetic spectrum. The quadrangle-shaped co-crystal constitutes a unique material that exhibits two-photon absorption and near-infrared emission simultaneously. This co-crystallization strategy holds considerable promise for the future design and synthesis of more advanced optical materials.
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This content will become publicly available on July 14, 2026
Scanning apparatus to detect the spectral directivity of optically emissive materials
An apparatus that records the optical spectrum of emissive materials as a function of polar coordinate angles is reported. The ability of the device to characterize the directive gain of a light source over the optical spectrum is demonstrated. The angular emission profile of an electrically driven LED with a hemispherical diffuser cap was measured. In addition, the device was used to characterize optically pumped materials exhibiting both fluorescence and amplified spontaneous emission, demonstrating its versatility for diverse emissive systems.
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- Award ID(s):
- 2337595
- PAR ID:
- 10615302
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 64
- Issue:
- 21
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. 6069
- Size(s):
- Article No. 6069
- Sponsoring Org:
- National Science Foundation
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