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The emerging optoelectronic material family of transition metal dichalcogenides may be useful in flexible electronics. However, only MoS₂ has been grown directly as thin films on polymer substrates, owing in part to the high deposition temperatures typically required to prepare these materials. Changing vapor deposition chemistry can allow much lower film growth temperatures. We show that when using tetrakis(dimethylamido)zirconium(IV), Zr(NMe₂)₄, and H₂S as precursors, low-temperature chemical vapor deposition affords films of zirconium(IV) sulfide (ZrS₂) directly on polymer substrates. Stoichiometric and crystalline ZrS₂ films can be deposited with good adhesion on polyimide (Kapton) and polyether ether ketone (PEEK) substrates at 150–200 °C. The films deposited on polydimethylsiloxane (PDMS) substrates were stoichiometric and crystalline, but not well adhered. Films on all substrates were polycrystalline with small (20–30 nm) grains, highly oriented in the [001] direction of the 1T ZrS₂ phase. The films grown on PEEK have resistivities ca. 625 Ω cm, two orders of magnitude higher than ZrS₂ films deposited at 800–1000 °C from ZrCl₄ and sulfur. The films grown on Kapton are similarly conductive, whereas films on PDMS are not conductive. 

We analyzed the surface of a freshly exfoliated single crystal of zirconium(IV) sulfide, ZrS₂. Survey spectra and high-resolution spectra from the core levels Zr 4p, Zr 4s, Zr 3d, Zr 3p, Zr 3s, S 2p, S 2s, O 1s, and C 1s were acquired. The binding energies and peak area ratios of a stoichiometric ZrS₂ single crystal provide a pure reference of well-defined composition for material deposited by chemical or physical vapor deposition methods. 

ABSTRACT Priority effects, where the order and timing of species arrival influence the assembly of ecological communities, have been observed in a variety of taxa and habitats. However, the genetic and molecular basis of priority effects remains unclear, hindering a better understanding of when priority effects will be strong. We sought to gain such an understanding for the nectar yeastMetschnikowia reukaufiicommonly found in the nectar of our study plant, the hummingbird‐pollinatedDiplacus(Mimulus)aurantiacus. In this plant,M.reukaufiican experience strong priority effects when it reaches flowers after other nectar yeasts, such asM.rancensis. After inoculation into two contrasting types of synthetic nectar simulating early arrival ofM.rancensis, we conducted whole‐transcriptome sequencing of 108 strains ofM.reukaufii. We found that several genes were differentially expressed inM.reukaufiistrains when the nectar had been conditioned by growth ofM.rancensis. Many of these genes were associated with amino acid metabolism, suggesting thatM.reukaufiistrains responded molecularly to the reduction in amino acid availability caused byM.rancensis. Furthermore, investigation of expression quantitative trait loci (eQTLs) revealed that genes involved in amino acid transport and resistance to antifungal compounds were enriched in some genetic variants ofM.reukaufii. We also found that gene expression was associated with population growth rate, particularly when amino acids were limited. These results suggest that intraspecific genetic variation in the ability of nectar yeasts to respond to nutrient limitation and direct fungal competition underpins priority effects in this microbial system.