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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 Thermodynamical and dynamical aspects of the climate system response to an-thropogenic forcing are often considered in two distinct frameworks: The former in the context of the forcing-feedback framework; the latter in the context of eddy-mean flow feedbacks and large-scale thermodynamic constraints. Here we use experiments with the dynamical core of a general circulation model (GCM) to provide insights into the relationships between these two frameworks. We first demonstrate that the climate feedbacks and climate sensitivity in a dynamical core model are determined by its prescribed thermal relaxation timescales. We then perform two experiments: One that explores the relationships between the thermal relaxation timescale and the climatological circulation; and a second that explores the relationships between the thermal relaxation timescale and the circulation response to a global warming-like forcing perturbation. The results indicate that shorter relaxation timescales (i.e., lower climate sensitivities in the context of a dynamical core model) are associated with 1) a more vigorous large-scale circulation, including increased thermal diffusivity and stronger and more poleward storm tracks and eddy-driven jets and 2) a weaker poleward displacement of the storm tracks and eddy-driven jets in response to the global warming-like forcing perturbation. Interestingly, the circulation response to the forcing perturbation effectively disappears when the thermal relaxation timescales are spatially uniform, suggesting that the circulation response to homogeneous forcing requires spatial inhomogeneities in the local feedback parameter. Implications for anticipating the circulation response to global warming and thermodynamic constraints on the circulation are discussed. 

Multimessenger searches for binary neutron star (BNS) and neutron star-black hole (NSBH) mergers are currently one of the most exciting areas of astronomy. The search for joint electromagnetic and neutrino counterparts to gravitational wave (GW)s has resumed with ALIGO’s, AdVirgo’s and KAGRA’s fourth observing run (O4). To support this effort, public semiautomated data products are sent in near real-time and include localization and source properties to guide complementary observations. In preparation for O4, we have conducted a study using a simulated population of compact binaries and a mock data challenge (MDC) in the form of a real-time replay to optimize and profile the software infrastructure and scientific deliverables. End-toend performance was tested, including data ingestion, running online search pipelines, performing annotations, and issuing alerts to the astrophysics community. We present an overview of the low-latency infrastructure and the performance of the data products that are now being released during O4 based on the MDC. We report the expected median latency for the preliminary alert of full bandwidth searches (29.5 s) and show consistency and accuracy of released data products using the MDC. We report the expected median latency for triggers from early warning searches (−3.1 s), which are new in O4 and target neutron star mergers during inspiral phase. This paper provides a performance overview for LIGO-Virgo-KAGRA (LVK) low-latency alert infrastructure and data products using theMDCand serves as a useful reference for the interpretation of O4 detections. 

Many microelectronic devices require thin films of silver or gold as wiring layers. We report silver( i ) and gold( i ) bicyclic amidinate complexes, wherein the constrained ligand geometry lessens the propensity for thermal decomposition. These new volatile compounds provide metallic films of silver and gold during CVD with hydrogen below 230 °C.