Pure N,N-dimethylformamide (DMF) and DMF−water mixtures are studied by molecular dynamics (MD) simulations. An OPLS all-atom force field is used for the simulation of DMF, revealing the local order and formation of the weak hydrogen bond of C−H···O, and TIP5P is adopted for the simulation of water and is compared with the latest X-ray and neutron diffraction experiment. Solution properties of DMF−water mixtures are investigated using radial distribution functions (RDFs) and hydrogen bonding properties. A significant composition dependence, which is attributed to the prevailing influence of the strongly polarizable amido of DMF and the clustering feature of water, is observed in the simulation. In addition, NMR experiments of DMF−water mixtures are used for the discussion of the hydrogen bonding effect. The results of the simulation are adopted to explain the NMR experiments by hydrogen bonding analysis. As a result, the magnetic anisotropy of the amido group is considered to play an important role in the chemical shift.

The magnetic and structural properties of InAs:Mn self-organized diluted magnetic quantum dots grown by low-temperature ͑ϳ270°C͒, solid-source molecular-beam epitaxy using a very low InAs growth rate ͑Ͻ0.1 ML/ s͒ are investigated. A Curie temperature ͑T C ͒ of ϳ350 K is measured in a sample grown with a Mn/ In flux ratio of 0.15. Electron energy-loss spectroscopy confirms that most of the Mn remains within the InAs quantum dots. We propose as a possible explanation for this high T C the effects of magnetic and structural disorder introduced by a random incorporation and inhomogeneous distribution of Mn atoms amongst the InAs quantum dots.

Localized surface plasmons (LSPs) are localized oscillations of free electrons in metal nanoparticles at optical frequencies. Confined mode profiles and near‐field enhancements make LSPs ultrasensitive to the dielectric environment, making them good candidates as sensors. The concept and applications have been generalized to spoof LSPs in microwave and terahertz frequencies, via plasmonic metamaterials composed of subwavelength corrugations. Herein, the basic physics, sensing prototypes, detection schemes, and state‐of‐the‐art progress are broadly reviewed from optical LSP sensing to microwave spoof LSP sensing. While optical LSPs exhibit localized sensitivity enhancement with high attenuation, spoof LSPs in microwave and terahertz frequencies combine the characteristics of deep‐subwavelength confinement and sensitivity enhancement of optical LSPs with low loss, high quality factor, multipole modes, and on‐chip detection of optical microcavities. Meanwhile, advances in printed circuits, integrated circuits, wireless communications, wearable devices, and Internet of things have endowed microwave sensing with a solid technical foundation and promising prospects. Applications in liquid sensing, gas sensing, and wearable sensing are demonstrated. Discussions are extended to electromagnetic sensing throughout the wave spectra, with concerns about key supporting technologies. The prospect of microwave sensing is emphatically investigated, specifically on leveraging the advantages of plasmonic enhancement.

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