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In nanoscale chemistry, magic-sized clusters (MSCs) stand out for their precise atomic configurations and privileged stability, offering unprecedented insights into the atomic-level structure of ligand-capped nanocrystals and a gateway to new synthesis and functionality. This article explores our efforts to shed light on the structure and reactivity of II-VI and III-V semiconductor MSCs. We have specifically been interested in the synthesis, isolation, and characterization of MSCs implicated as key intermediates in the synthesis of semiconductor quantum dots. Our exploration into their synthesis, structure, transformation, and reactivity provides a roadmap to expand the scope of accessible semiconductor clusters with diverse structures and properties. It paves the way for tailor-made nanomaterials with unprecedented atom-level control. In these studies, atomic level structure has been deduced through advanced characterization methods, including single-crystal and powder X-ray diffraction, complemented by pair distribution function analysis, nuclear magnetic resonance spectroscopy, and vibrational spectroscopy. We have identified two distinct families of CdSe MSCs with zincblende and wurtzite-like structures. We have also characterized two members of the wurtzite-like family of InP clusters and a related InAs cluster. Our research has revealed intriguing structural homologies between II-VI and III-V MSCs. These findings contribute to our fundamental understanding of semiconductor MSCs and hint at broader implications for phase control at the nanoscale and the synthesis of novel nanomaterials. We have also explored three distinct pathways of cluster reactivity, including cluster interconversion mediated by controlling the chemical potential of the reaction environment, both seeded and single source precursor growth mechanisms to convert MSCs into larger nanostructures, and cation exchange to access new cluster compositions that are precursors to nanocrystals that may be challenging or impossible to access from traditional bottom-up nucleation and growth. Together with the collective efforts of other researchers in the field of semiconductor cluster chemistry, our work establishes a strong foundation for predicting and controlling the form and function of semiconductor MSCs. By highlighting the role of surface chemistry, stoichiometry, and dopant incorporation in determining cluster properties, our work opens exciting possibilities for the design and synthesis of new materials. The insights gained through these efforts could significantly impact the future of nanotechnology, particularly in areas like photonics, electronics, and catalysis. 

Intrinsic active site ensembles on Ni₂P nanocrystal surfaces direct the selective reduction of nitrate to ammonia through the potential-dependent co-adsorption of H* and NO_x*. 

This tutorial review presents our perspective on designing organic molecules for the functionalization of inorganic nanomaterial surfaces, through the model of an “anchor-functionality” paradigm. This “anchor-functionality” paradigm is a streamlined design strategy developed from a comprehensive range of materials ( e.g. , lead halide perovskites, II–VI semiconductors, III–V semiconductors, metal oxides, diamonds, carbon dots, silicon, etc. ) and applications ( e.g. , light-emitting diodes, photovoltaics, lasers, photonic cavities, photocatalysis, fluorescence imaging, photo dynamic therapy, drug delivery, etc. ). The structure of this organic interface modifier comprises two key components: anchor groups binding to inorganic surfaces and functional groups that optimize their performance in specific applications. To help readers better understand and utilize this approach, the roles of different anchor groups and different functional groups are discussed and explained through their interactions with inorganic materials and external environments. 

Abstract A key obstacle for all quantum information science and engineering platforms is their lack of scalability. The discovery of emergent quantum phenomena and their applications in active photonic quantum technologies have been dominated by work with single atoms, self‐assembled quantum dots, or single solid‐state defects. Unfortunately, scaling these systems to many quantum nodes remains a significant challenge. Solution‐processed quantum materials are uniquely positioned to address this challenge, but the quantum properties of these materials have remained generally inferior to those of solid‐state emitters or atoms. Additionally, systematic integration of solution‐processed materials with dielectric nanophotonic structures has been rare compared to other solid‐state systems. Recent progress in synthesis processes and nanophotonic engineering, however, has demonstrated promising results, including long coherence times of emitted single photons and deterministic integration of emitters with dielectric nano‐cavities. In this review article, these recent experiments using solution‐processed quantum materials and dielectric nanophotonic structures are discussed. The progress in non‐classical light state generation, exciton‐polaritonics for quantum simulation, and spin‐physics in these materials is discussed and an outlook for this emerging research field is provided.