John Stuart Anderson

A benzenetetrathiolate-bridged dinuclear platinum(diimine)(dithiolene) complex exhibits unprecedented deep near-infrared luminescence (1172 nm) upon two-electron oxidation.

We report an end-to-end computational-experimental workflow for the discovery of metal–organic frameworks (MOFs), demonstrated by the computational design and synthesis of two novel Zn-based frameworks, UCHI-1 and UCHI-2, exhibiting enhanced methane uptake and selectivity at low pressure under ambient conditions (298 K, 1 bar). The workflow enables the rational selection and experimental realization of metal–organic frameworks combining data mining, machine-learning driven adsorption prediction, and structure generation, with experimental synthesis and validation within a closed-loop discovery pipeline. Analysis of existing and newly generated MOFs reveals the structure–property relationships governing low-pressure methane adsorption, identifying an optimal pore size and shape, framework densities, linker functionalities, and framework topologies that maximize dispersive C–H/π and van der Waals interactions. Beyond the specific materials identified herein, the results establish this workflow as a scalable and extensible platform for accelerated MOF discovery, with clear routes toward further optimization and automation while demonstrating practical applicability beyond purely theoretical exploration of hypothetical materials.

Metal nitrides represent a large class of materials with extensive applications in optoelectronics, energy and healthcare technologies. For example, GaN and related nitride semiconductors are key materials for solid-state lighting and high-power electronics^1,2. TiN and other early transition metal nitrides (TMNs) are widely used in wear-resistant alloys, tool coatings, catalysts and medical implants³. Strong metal-nitrogen bonds grant nitrides structural rigidity as well as chemical and thermal stability⁴. However, the covalency of metal-nitrogen bonds necessitates high temperatures to synthesize crystalline metal nitrides. Common synthetic routes include high-temperature solid-state nitridation⁵, crystal growth in supercritical ammonia⁶, molecular-beam epitaxy (MBE)⁷, reactive sputtering^8,9 and chemical vapour deposition^1,10-12. The solution synthesis of colloidal nanocrystals (NCs) has been demonstrated for late TMNs with relatively weak chemical bonds^13-17, whereas the synthesis of early TMN NCs is challenging because it requires temperatures far above the stability range of commonly used solvents. Here we report a general approach to solution synthesis of refractory metal nitride NCs by reacting metal halides and ammonia dissolved in molten inorganic salts at elevated pressures. Successful syntheses of colloidal TiN, VN, GaN, NbN, Mo₂N, Ta₃N₅, TaN, W₂N and ternary Ti_1-xV_xN NCs are demonstrated. These NCs expand the scope of solution-processable technologically important materials.

A (tBu,TolDHP)Cu complex is reported as an electrocatalyst for alkyne semihydrogenation and carbonyl reduction. Mechanistic investigations reveal the catalyst proceeds through intermediates where the storage of H2 across the ligand backbone enables substrate activation and reduction. This is the first reported homogeneous Cu catalyst for electrocatalytic semihydrogenation and carbonyl reduction.

Fe₄S₄ clusters play essential roles in nature, classically in electron transport but increasingly in newly discovered reactivity or catalysis. These roles have spurred interest in developing synthetic Fe₄S₄ systems and while several molecular and material systems built from Fe₄S₄ clusters have been developed, comparatively few examples of synthetic Fe₄S₄ cluster-based catalysts exist. Herein, we present the use of an Fe₄S₄-based coordination polymer as a catalyst for the direct and selective electroreduction of CO₂ to CO. Computational studies suggest that the reaction proceeds through CO₂ binding to a reduced Fe₄S₄ cluster, followed by a series of protonation, reduction, and H₂O loss steps to yield a CO-bound cluster that can finally exchange with CO₂ to restart the catalytic cycle. CO bound clusters are predicted to be thermodynamically stable, suggesting that carbonyl species might be off-cycle intermediates. Mechanistic CV studies as well as in situ studies by IR spectroscopy provide evidence for carbonyl-ligated clusters, supporting these compounds as unusual examples of small molecule binding to Fe₄S₄ clusters. This work establishes Fe₄S₄ cluster-based coordination polymers as direct electrocatalysts for CO₂ reduction and provides mechanistic insights into how these species mediate catalytic conversions of small molecules.

Near-infrared (NIR) emissive fluorophores are appealing for biological imaging and sensing applications, particularly in the lower-energy NIR-II region (1000-1700 nm). Compared to light in the visible and NIR-I regions, NIR-II light undergoes less absorption and scattering by biological tissues, enabling deeper tissue-penetration and higher imaging resolution. Tetrathiafulvalene-tetrathiolate (TTFtt)-bridged bimetallic diradicaloid complexes exhibit bright NIR-II emission with high photoluminescence quantum yields (PLQYs) relative to other NIR-II fluorophores. These complexes are also particularly modular, as the capping ligands on the metal centers can be substituted to impart desired properties. Here, azide-functionalized bis(imino)acenaphthene (BIAN) capping ligands are introduced to leverage and expand this modularity. BIAN-capped TTFtt complexes exhibit chemical and photophysical properties comparable with previously reported TTFtt complexes. BIAN backbones functionalized with an azide group further enable Huisgen cycloaddition "click" chemistry for the attachment of diverse functional moieties while preserving the intrinsic NIR-II photophysical properties of the TTFtt core. As one example, a sulfonate clicked TTFtt complex (1-C3) displays enhanced solubility and increased photoluminescence (PL) intensity in aqueous solutions compared to other TTFtt complexes. Notably, 1-C3 also exhibits pH-dependent PL intensity, suggesting its potential utility as an NIR-II-emitting pH sensor. Overall, these results demonstrate the dramatically expanded modularity of TTFtt complexes through the use of clickable-BIAN ligands.

Fe₄S₄ clusters play essential roles in nature, classically in electron transport but increasingly in newly discovered reactivity or catalysis. These roles have spurred interest in developing synthetic Fe4S4 systems and while several molecular and material systems based on Fe₄S₄ clusters have been developed, comparatively few examples of synthetic Fe₄S₄ cluster-based catalysts exist. Herein, we present the use of an Fe₄S₄-based coordination polymer as a catalyst for the direct and selective electroreduction of CO2 to CO. Computational studies suggest that the reaction proceeds through CO2 binding to a reduced Fe4S4 cluster, followed by a series of protonation, reduction, and H2O loss steps to yield a CO-bound cluster that can finally exchange with CO2 to restart the catalytic cycle. CO bound clusters are predicted to be thermodynamically stable, suggesting that carbonyl species might be off-cycle intermediates. Mechanistic CV studies as well as in situ studies by IR spectroscopy provide evidence for carbonyl-ligated clusters, supporting these compounds as unusual examples of small molecule binding to Fe4S4 clusters. This work establishes Fe4S4 cluster-based coordination polymers as direct electrocatalysts for CO2 reduction and provides mechanistic insights into how these clusters mediate catalytic conversions of small molecules.

One of the main challenges facing quantum information science (QIS) is the development of robust qubits that can be operated under ambient conditions. Current state-of-the-art anionic nitrogen-vacancy center (NV^-) defect qubits are robust enough to be operated at room temperature but lack scalability and tunability. These are areas where molecular qubits excel, although, in contrast, they typically suffer from poor air stability and fast decoherence at elevated temperatures and in magnetically noisy environments. Organic-based systems offer possible advantages to this end, although examples retaining room temperature coherence are still rare. Furthermore, most organic-based systems lack optical transitions similar to NV^- centers that could allow for optical initialization and readout. Here we report two new organic-based qubit candidates that demonstrate room temperature coherence in nuclear and electron spin-rich environments. These qubits luminesce far into the near-infrared (NIR, 700-1700 nm) and telecom (∼1260-1625 nm) regions, ideal for biological sensing and communications applications, respectively.

The diverse structures of metal-organic frameworks (MOFs) originate from the coordination chemistry of ionic metal-ligand bonds, while covalent organic frameworks (COFs) leverage covalent bonding. Between these extremes, extended structures based on metalloids are comparatively rare. This paucity obscures how the chemistry of the metalloid elements, intermediate between the metals and the main group, manifests in the properties of new porous materials. This study presents the chemistry of new examples of germanium-organic frameworks (GeOFs). Two new GeOFs with metalloid GeO4 nodes and redox-active triphenylene hexahydroxyl (THO) linkers, Ge-THO-1 and Ge-THO-2, have been synthesized and characterized. Ge-THO-1 has Ge2+ nodes which become tetravalent with concomitant formation of Ge–Ge bonds in Ge-THO-2 upon activation or air exposure. This structural transformation leads to a 10,000-fold increase in electrical conductivity. These materials are rare examples of GeOFs as well as a unique case where metal-metal bond formation regulates structure and conductivity in porous materials.