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![Piezoresponse force microscopy detects the co-existence of multiple polarization states in van-der-Waals layered CuInP2S6. Depending on the location of the Cu atoms (blue spheres), the piezoelectric properties of the material can be tuned.](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture1_2.png?h=e0905d39&itok=2gi30Ht8)
Discovered quadruple-well ferroelectricity in layered CuInP2S6 crystals based on a structural phase that doubles electrostatic polarization enabled by the van der Waals gap.
![A snapshot of liquid electrolyte structure is shown, as determined by molecular dynamics simulation (left). The Van Hove function, determined by inelastic X-ray scattering of an aqueous NaBr solution is shown (right). Correlated motions of water, cation, and anion in pico-second timescale are disentangled through the partial Van Hove functions.](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture2_0.png?h=ff4f4b66&itok=Z0Pb_D--)
Correlated motions of water molecules and salt ions in real space and time were visualized through the Van Hove function.
![Luminescent Se clusters in pulsed laser deposition plasma plumes are imaged as they are controllably slowed to < 5 eV/atom to replace the top S atoms in monolayer WS2 to form Janus WSSe monolayers, which are verified by dark-field atomic resolution electron microscopy in tilted geometry (inset).](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture3_0.png?h=d3a57f01&itok=HNd5VDpe)
Selective replacement of the top atoms of an atomically thin 2D crystal to form Janus monolayers has been achieved by hyperthermal implantation of clusters generated by laser ablation.
![The schematic shows the spin Hall effect by critical spin fluctuations. Electrons driven by an external electric field (charge current jc shown as a yellow arrow) are deflected transversely depending on their spin direction, generating transverse spin current js shown as a pink arrow. The size of js increases as fluctuating local spin moments rapidly develop ferromagnetic correlations.](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture4_1.png?h=125a180f&itok=EooA997J)
New mechanisms for spin Hall effect are theoretically developed based on the critical ferromagnetic fluctuation of magnetic moments.
![Constructing libraries of atomic defects (such as those shown above in graphene) relied on an approach that combined experiment and theory to extract and classify defects with STEM, predict electronic structure with DFT, and compare both of these experimental and theoretical results with STM results from the same system.](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture8_0.png?h=6e835914&itok=-rVHgfJG)
Developed a deep-learning approach to automatically create libraries of structural and electronic properties of atomic defects in 2D materials.
![Early Signal of Emerging Deformation and Collectivity in Atomic Nuclei](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture1_1.png?h=d4aafce0&itok=enPF9Jql)
Pillar[5]quinone derived multi-microporous organic polymers with hydrophenazine linkages (MHP-P5Q) were synthesized via a solvent and catalyst-free mechanochemical
![Vibrational sum frequency generation spectra and schematic of surface ordering and packing of ODMS-MIM(+) headgroups and tails at the organic/aqueous interface as functions of increasing ionic strength (NaCl concentration).](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture2.png?h=897e9f9e&itok=UOJZtJ10)
We show that hydrogen bonding and electrostatic interactions in the aqueous phase control the conformations of the polymers in the organic phase.
![An artistic rendition of the type of diffusive path a molecule in solution may take before adsorbing on a surface.](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture3.png?h=48aad3b8&itok=fsHJ4T6i)
A new method based on molecular dynamics simulations and kinetic theory can predict the rate of molecules adsorbing to a surface from liquid.
![INS and IR discriminate the role of OH and H- for acetylene Semi-hydrogenation over ceria](/sites/default/files/styles/list_page_thumbnail/public/2020-07/Picture4.png?h=4c804e8b&itok=ADu6kjmA)
In situ inelastic neutron scattering (INS) and IR spectroscopy provide the first direct evidence for the catalytic roles of cerium hydride (Ce-H) and hydroxyl group (OH) groups in acetylene hydrogenation over ceria as a function of the density