Localized surface plasmon resonances were controlled at deep-ultraviolet (DUV) wavelengths by fabricating aluminum (Al) nanostructures in a size-controllable manner. Plasmon resonances were obtained at wavelengths from near-UV down to 270 nm (4.6 eV) depending on the fabricated structure size. Such precise size control was realized by the nanosphere lithography technique combined with additional microwave heating to shrink the spaces in a close-packed monolayer of colloidal nanosphere masks. By adjusting the microwave heating time, the sizes of the Al nanostructures could be controlled from 80 nm to 50 nm without the need to use nanosphere beads of different sizes. With the outstanding controllability and versatility of the presented fabrication technique, the fabricated Al nanostructure is promising for use as a DUV plasmonic substrate, a light-harvesting platform for mediating strong light-matter interactions between UV photons and molecules placed near the metal nanostructure. V

The dielectric constant of indium in the deepultraviolet (DUV) region satisfies the conditions for localized surface plasmon resonance with low absorption loss. We report that indium acts as an agent of efficient surface-enhanced resonance Raman scattering (SERRS) in the DUV. Indium-coated SERRS substrates were prepared by depositing indium on fused silica glass substrates with control of the deposition thickness to tailor the plasmon resonance in the DUV. With excitation at 266 nm, SERRS was observed from thin adenine films deposited on the indiumcoated substrates, and the signal intensity was up to 11 times higher than that of a bare fused silica glass substrate. FDTD calculations showed that an enhanced electromagnetic field can be locally generated on the indium-coated substrates. Considering the volume of the enhanced field region in the excitation spot, we estimated the average enhancement factor to be 10 2 or higher. Our results indicate that indium is a promising and easy-to-use metal for efficiently exciting DUV-SERRS of samples containing a small number of molecules. KEYWORDS: indium, surface-enhanced resonance Raman scattering, localized surface plasmon resonances, deep-ultraviolet S urface-enhanced Raman scattering (SERS) is useful for label-free, nondestructive detection and analysis of samples containing a small number of molecules, 1−3 even single molecules. 4,5 Since its discovery in 1974, 6 SERS research has resulted in a large number of papers, exceeding 11 000, 7 mostly related to visible or near-infrared (NIR) light excitation. Recently, small but growing efforts have been made to extend SERS to the deep-ultraviolet (DUV) region. DUV excitation makes SERS more powerful for high S/N measurement of a small number of molecules. The advantages of DUV excitation are notable when measuring aromatic compounds such as nucleotide bases 8 and aromatic amino acid residues, 9 which are essential in biology. The scattering efficiency of these molecules is up to 10 6 times higher with DUV excitation compared with visible and NIR excitation 10 due to the resonance Raman effect. Additionally, DUV excitation can be used to distinguish Raman bands from native fluorescence of a sample in a spectrum. 11Furthermore, since the light-scattering efficiency is inversely proportional to the fourth power of the wavelength, DUV excitation can give a 10−100 times stronger Raman scattering signal from any off-resonance molecule than visible and NIR excitation can.Resonance excitation of localized surface plasmon polaritons (LSPPs) in metals is required for SERS.12−15 Silver and gold, metals commonly used for SERS, cannot support the excitation of LSPPs in the DUV. 16 To extend SERS to the DUV, it is essential to explore DUV plasmonic metals, in which surface plasmons are resonantly excited by DUV light. So far, aluminum is recognized as the only reliable and efficient DUV plasmonic metal.16−32 The usefulness of aluminum as a medium of LSPPs in the DUV was first demonstrated in 2007 via extraordinary optical tran...

Hydrocarbons (HCs) are environmentally friendly natural refrigerants and are expected to be promising alternative candidates to replace some currently used halogenated hydrocarbon refrigerants. Some available data sets for HCs used to formulate the equations of state (EoS) for them are relatively old, so we point out that new data with less uncertainty are expected to play an essential role in updating the EoS for HCs. Therefore, a set of PVT property measurements for hydrocarbon refrigerants including propane, n-butane, and isobutane was conducted in the present study. A newly developed vibrating-tube densimeter was employed for the measurements, and then a total of 430 liquid PVT properties were obtained, including those at the saturation boundaries. The measurement range is (240 to 380) K for temperature and up to 7 MPa for pressure. The measurement uncertainty is about 3 mK for temperature, 0.26 kPa + 0.022% for pressure, and 0.1 kg‚m -3 + 0.024% for density. The present data were compared with available thermodynamic models that are currently considered to be the most reliable. A set of modified Tait equations of state for the liquid phase are also discussed.

2 D NMR spectra for partially deuterated (CH 3 ND 3 ) 3 Bi,Br 9 showed that the phase transitions in this compound are related to the motion of the methylammonium cations. Single-crystal X-ray work at room temperature shows that the space group for [N(CH 3 ) 4 ] 3 Sb 2 Cl 9 is_P6 3 /mmc with a = 925.1 pm, c = 2173.4 pm, Z = 2. For (CH 3 NH 3 ) 3 Sb 2 Br 9 the space group is P3ml with a = 818.8 pm, c = 992.7 pm, Z = 1; in both cases the cations show dynamical disorder. The Rietveld analysis of the powder X-ray diffraction for (CH 3 NH 3 ) 3 Bi 2 Br 9 reveals the space group P3ml with a = 821.0, c -1000.4 pm, Z = 1 at room temperature; the compound is isomorphous with (CH 3 NH 3 ) 3 Sb 2 Br 9 . The crystal symmetries of the low-temperature phases of (CH 3 NH 3 ) 3 Bi 2 Br 9 and [N(CH 3 ) 4 ] 3 Bi 2 Br 9 were deduced from the results of the NQR spectroscopy.

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