A series of luminescent frameworks was synthesized from the selective combination of aggregation induced emission (AIE)-linker tetra-(4-carboxylphenyl)ethylene (H 4 TCPE) and Zn 2 + . Complex 1 was formed by the close packing of Zn-TCPE hinge, and isostructural complexes 2-5 were constructed by the linkage of Zn-TCPE layer and pillar ligands. These complexes exhibit highly efficient multiphoton excited photoluminescence (MEPL) and concomitant thirdharmonic generation (THG). The multiphoton absorption (MPA) parameters of 1 are superior to other multiphoton emission materials including the perovskite nanocrystals. The incorporation of pillar linkers slows down the charge transfer between layers of Zn-TCPE, and the aromatic core of pillar linkers has a great influence on the MPA performance of the corresponding frameworks.

Looking for materials with compelling nonlinear optical (NLO) response is of great importance for next-generation nonlinear nanophotonics. We demonstrate an escalated two-photon absorption (TPA) in ultrasmall niobium carbide quantum dots (Nb2C QDs) that is induced by a two-even-parity states transition. The TPA response of Nb2C QDs was observed in the near-infrared band of 1064–1550 nm. Surprisingly, at 1064 nm, Nb2C QDs shows an enhanced TPA response than other wavelengths with a nonlinear absorption coefficient up to a value of 0.52 ± 0.05 cm/GW. Additionally, the nonlinear optical response of Nb2C changes to saturable absorption when the incident wavelength is between 400–800 nm wavelength. Density functional theory (DFT) validates that TPA, induced by two even-parity states transition, breaks the forbidden single-photon transition, enabling a tremendous TPA response in Nb2C QDs at 1064 nm. It offers the possibility of manipulating the NLO response of Nb2C via morphology or surface termination.

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Zn‐AIEgen crystalline frameworks exhibit highly efficient multiphoton excited photoluminescence and concomitant third‐harmonic generation. Exploration of the structural–optical relationship provides a useful methodology for the design of better high‐performance multiphoton absorption materials, as reported by Jagadese J. Vittal, Jianzhuang Jiang et al. in their Research Article (e202115205).

Kristalline Zn‐AIEgen‐Gerüste zeigen eine hocheffiziente multiphotonenangeregte Photolumineszenz einhergehend mit Obertonbildung. Die Erforschung der strukturell‐optischen Beziehungen liefert eine nützliche Methodik für die Entwicklung besserer Hochleistungs‐Multiphotonenabsorptionsmaterialien, wie Jagadese J. Vittal, Jianzhuang Jiang et al. in ihrem Forschungsartikel erläutern (e202115205).