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The identification ability of nanopore sequencing is severely hindered by the diversity of amino acids in a protein. To tackle this problem, a graphene nanoslit sensor is adopted to collect force and current signals to distinguish 20 residues. Extensive molecular dynamics simulations are performed on sequencing peptides under pulling force and applied electric field. Results show that the signals of force and current can be simultaneously collected. Tailoring the geometry of the nanoslit sensor optimizes signal differences between tyrosine and alanine residues. Using the tailored geometry, the characteristic signals of 20 types of residues are detected, enabling excellent distinguishability so that the residues are well-grouped by their properties and signals. The signals reveal a trend in which the larger amino acids have larger pulling forces and lower ionic currents. Generally, the graphene nanoslit sensor can be employed to simultaneously sense two signals, thereby enhancing the identification ability and providing an effective mode of nanopore protein sequencing.Organophosphorus compounds are a wide and diverse class of chemicals playing a crucial role in living organisms. This aspect has been often investigated using nuclear magnetic resonance (NMR), which provides information about molecular structure and function. In this paper, we report the results of theoretical and experimental studies on basic organophosphorus compounds using zero-field NMR, where spin dynamics are investigated in the absence of a magnetic field with the dominant heteronuclear J-coupling. We demonstrate that the zero-field NMR enables distinguishing the chemicals owing to their unique electronic environment even though their spin systems have the same alphabetic designation. Such information can be obtained just in a single measurement, while amplitudes and widths of observed low-field NMR resonances enable the study of processes affecting spin dynamics. An excellent agreement between simulations and measurements of the spectra, particularly in the largest frequency J-couplings range ever reported in zero-field NMR, is demonstrated.Empirical fitting of parameters in approximate density functionals is common. Such fits conflate errors in the self-consistent density with errors in the energy functional, but density-corrected DFT (DC-DFT) separates these two. selleckchem We illustrate with catastrophic failures of a toy functional applied to H2+ at varying bond lengths, where the standard fitting procedure misses the exact functional; Grimme's D3 fit to noncovalent interactions, which can be contaminated by large density errors such as in the WATER27 and B30 data sets; and double-hybrids trained on self-consistent densities, which can perform poorly on systems with density-driven errors. In these cases, more accurate results are found at no additional cost by using Hartree-Fock (HF) densities instead of self-consistent densities. For binding energies of small water clusters, errors are greatly reduced. Range-separated hybrids with 100% HF at large distances suffer much less from this effect.Synthesis of the unconventional phase of noble metal nanocrystals may create new opportunities in exploring intriguing physicochemical properties but remains challenging. In the research field of thin film growth, the interface strain offers a general driving force to stabilize the metastable phase of epitaxial film. Herein we extend this concept to the field of noble metal nanocrystals and report the solution synthesis of metastable face-centered tetragonal Au that has not been discovered before. The successful synthesis relies on the formation of intermetallic AuCu3@Au core-shell structure, where the interface strain stabilizes the metastable fct Au overlayer. Compared with the face-centered cubic Au counterpart, the metastable fct Au shows greatly improved catalytic activity toward CO2 reduction to CO. The density functional theory calculations and spectroscopic studies reveal that the metastable fct Au upshifts the d-band center, which lowers the energy barrier of key intermediate COOH* formation and thus facilitates the reaction kinetics.Room temperature ionic liquids (RTILs) have a wide range of current and potential applications, in areas ranging from supercapacitor energy storage to sequestration of toxic gas phase species and use as reusable solvents for selected organic reactions. All these applications stem from their unique physical and chemical properties, which remain understood to only a limited extent. Among the issues of greatest importance is the extent to which RTILs exist as dissociated ionic species and the length scales over which some types of organizations are seen to exist in them. In this Invited Feature Article, we review the current understanding of organization in this family of materials, where opportunities lie in terms of deepening our understanding, and what potential applications would benefit from gaining such knowledge.Corrosion of metals in atmospheric environments is a worldwide problem in industry and daily life. Traditional anticorrosion methods including sacrificial anodes or protective coatings have performance limitations. Here, we report atomically thin, polycrystalline few-layer graphene (FLG) grown by chemical vapor deposition as a long-term protective coating film for copper (Cu). A six-year old, FLG-protected Cu is visually shiny and detailed material characterizations capture no sign of oxidation. The success of the durable anticorrosion film depends on the misalignment of grain boundaries between adjacent graphene layers. Theoretical calculations further found that corrosive molecules always encounter extremely high energy barrier when diffusing through the FLG layers. Therefore, the FLG is able to prevent the corrosive molecules from reaching the underlying Cu surface. This work highlights the interesting structures of polycrystalline FLG and sheds insight into the atomically thin coatings for various applications.Mixed fluids confined in porous solid hosts present challenges for the accurate characterization of individual-component behavior. NMR diffusometry with chemical resolution is used to identify unexpected loading- and composition-dependent anomalous diffusion in water/cyclohexane mixtures confined to solid nanoporous glass (NPG) hosts. Diffusion NMR results indicate that data obtained on pure-component liquids in confinement cannot be extrapolated to their nonideal liquid mixtures confined in the same solid host. Loading-dependent data must be obtained on each component in the confined mixture in order to determine which of the liquid components exhibits chemical affinity for the host and, conversely, which of the components exhibits anomalous diffusivity. Most notably, NMR diffusometry revealed that cyclohexane diffusivity varied by 2 orders of magnitude in a water-rich mixture depending on the total fluid loading in the NPG host, ranging from anomalously high diffusivities that significantly exceeded that for pure cyclohexane in NPG at low fluid loadings to kinetically trapped sequestration at high fluid loadings.