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Interest in inorganic ternary nitride materials has grown rapidly over the past few decades, as their diverse chemistries and structures make them appealing for a variety of applications. Due to synthetic challenges posed by the stability of N 2 , the number of predicted nitride compounds dwarfs the number that has been synthesized, offering a breadth of opportunity for exploration. This review summarizes the fundamental properties and structural chemistry of ternary nitrides, leveraging metastability and the impact of nitrogen chemical potential. A discussion of prevalent defects, both detrimental and beneficial, is followed by a survey of synthesis techniques and their interplay with metastability. Throughout the review, we highlight applications (such as solid-state lighting, electrochemical energy storage, and electronic devices) in which ternary nitrides show particular promise. 

Photoinduced electron transfer into mesoporous oxide substrates is well-known to occur efficiently for both singlet and triplet excited states in conventional metal-to-ligand charge transfer (MLCT) dyes. However, in all-organic dyes that have the potential for producing two triplet states from one absorbed photon, called singlet fission dyes, the dynamics of electron injection from singlet vs. triplet excited states has not been elucidated. Using applied bias transient absorption spectroscopy with an anthradithiophene-based chromophore ( ADT-COOH ) adsorbed to mesoporous indium tin oxide ( nanoITO ), we modulate the driving force and observe changes in electron injection dynamics. ADT-COOH is known to undergo fast triplet pair formation in solid-state films. We find that the electronic coupling at the interface is roughly one order of magnitude weaker for triplet vs. singlet electron injection, which is potentially related to the highly localized nature of triplets without significant charge-transfer character. Through the use of applied bias on nanoITO : ADT-COOH films, we map the electron injection rate constant dependence on driving force, finding negligible injection from triplets at zero bias due to competing recombination channels. However, at driving forces greater than −0.6 eV, electron injection from the triplet accelerates and clearly produces a trend with increased applied bias that matches predictions from Marcus theory with a metallic acceptor. 

Abstract. Insoluble atmospheric aerosol, such as mineral dust, hasbeen identified as an important contributor to the cloud droplet numberconcentration and indirect climate effect. However, empirically derivedFrenkel–Halsey–Hill (FHH) water adsorption parameters remain the largestsource of uncertainty in assessing the effect of insoluble aerosol onclimate using the FHH activation theory (FHH-AT). Furthermore, previouslyreported FHH water adsorption parameters for illite and montmorillonitedetermined from water adsorption measurements below 100 % RH do notsatisfactorily agree with values determined from FHH-AT analysis ofexperimental cloud condensation nuclei (CCN) measurements undersupersaturated conditions. The work reported here uses previously reportedexperimental water adsorption measurements for illite and montmorilloniteclays (Hatch et al., 2012, 2014) to show that improvedanalysis methods that account for the surface microstructure are necessaryto obtain better agreement of FHH parameters between water adsorption andexperimental CCN-derived FHH parameters.