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The weakly bound Ne·HCl van der Waals dimer is a prototype for studying large-amplitude motion in noncovalently bound systems. We report the microwave spectrum of eight isotopologues of Ne·HCl, five of which have not previously been observed by high-resolution spectroscopy. We examine trends in experimentally derived van der Waals stretching force constants and effective bond lengths that are strongly sensitive to isotopologue-dependent motional averaging along the hindered rotation coordinate. Finally, we report an updated semi-empirical three-dimensional morphed potential for the Ne·HCl dimer that is fitted to a large dataset including previous microwave, near-IR, and sub-millimeter wave data in addition to our new microwave data. 

Abstract On 18 November 2022, a large earthquake struck offshore southern Sumatra, generating a tsunami with 25 cm peak amplitude recorded at tide gauge station SBLT. OurW‐phase solution indicates a shallow dip of 6.2°, compatible with long‐period surface wave radiation patterns. Inversion of teleseismic body waves indicates a shallow slip distribution extending from about 10 km deep to near the trench with maximum slip of ∼4.1 m and seismic moment of  Nm (M_W7.3). Joint modeling of seismic and tsunami data indicates a shallow rigidity of ∼23 GPa. We find a low moment‐scaled radiated energy of , similar to that of the 2010M_W7.8 Mentawai event () and other tsunami earthquakes. These characteristics indicate that the 2022 event should be designated as a smaller moment magnitude tsunami earthquake compared to the other 12 well‐documented global occurrences since 1896. The 2022 event ruptured up‐dip of the 2007M_W8.4 Bengkulu earthquake, demonstrating shallow seismogenic capability of a megathrust that had experienced both a deeper seismic event and adjacent shallow aseismic afterslip. We consider seismogenic behavior of shallow megathrusts and concern for future tsunami earthquakes in subduction zones globally, noting a correlation between tsunami earthquake occurrence and subducting seafloor covered with siliceous pelagic sediments. We suggest that the combination of pelagic clay and siliceous sediments and rough seafloor topography near the trench play important roles in controlling the genesis of tsunami earthquakes along Sumatra and other regions, rather than the subduction tectonic framework of accretionary or erosive margin. 

Based on measurements of near-trench deformations of the oceanic and overriding plates, in this investigation, we elucidate the tectonic and mechanical processes leading to the Mw>7.0 (moment magnitude of 7.0) Acapulco, Mexico, earthquake in 2021. We exploit unprecedented ocean-bottom observations using ultralong-period “tilt mechanical amplifiers,” along with hydrostatic pressure, global navigation satellite system, and satellite interferometric synthetic aperture radar data. The joint inversion of these geodetic data, template-matching seismicity, and repeating earthquakes revealed the first two shallow slow slip events (SSEs) observed in Mexico. The first one migrated from the trench to the earthquake hypocenter before rupture, and the second one occurred following an Mw>7.3 long-term SSE induced by the earthquake. Episodic near-trench oceanic-crust deformations (i.e., tilt transients) associated with shallow and deep synchronous decoupling of the plate interface reveal the occurrence of “slab-pull surges” before three regional earthquakes of magnitude 7 or greater, including the Acapulco event, suggesting that they may serve as rupture precursors observable in subduction zones. 

The digital alchemy framework is an extended ensemble simulation technique that incorporates particle attributes as thermodynamic variables, enabling the inverse design of colloidal particles for desired behavior. Here, we extend the digital alchemy framework for the inverse design of patchy spheres that self-assemble into target crystal structures. To constrain the potentials to non-trivial solutions, we conduct digital alchemy simulations with constant second virial coefficient. We optimize the size, range, and strength of patchy interactions in model triblock Janus spheres to self-assemble the 2D kagome and snub square lattices and the 3D pyrochlore lattice, and demonstrate self-assembly of all three target structures with the designed models. The particles designed for the kagome and snub square lattices assemble into high quality clusters of their target structures, while competition from similar polymorphs lower the yield of the pyrochlore assemblies. We find that the alchemically designed potentials do not always match physical intuition, illustrating the ability of the method to find nontrivial solutions to the optimization problem. We identify a window of second virial coefficients that result in self-assembly of the target structures, analogous to the crystallization slot in protein crystallization. 

The 2022 Tonga eruption produced ground motions dominated by force interactions between the solid Earth and atmosphere. 

Abstract We draw from ecological systems and social psychological theories to elucidate macrosystem‐ and microsystem‐level variables that promote and maintain gender inequities in science, technology, engineering, and math (STEM). Because gender‐STEM stereotypes undermine girls’ (and women's), but boosts boys’ (and men's), STEM interest and success, we review how they operate in STEM learning environments to differentially socialize girls and boys and undermine gender integroup relations. We propose seven practice recommendations to improve STEM K‐12 education: (1) design relational classrooms, (2) teach the history of gender inequality and bias, (3) foster collaborative and cooperative classrooms, (4) promote active learning and growth mindset strategies, (5) reframing STEM as inclusive, (6) create near‐peer mentorship programs, and (7) re‐imagine evaluation metrics. To support these practice recommendations, three policy recommendations are posited: (1) increase teacher autonomy, training, and representation, (2) re‐evaluate standardized testing, and (3) reallocate and increase government funding for public schools.