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Two-dimensional double nanoparticle (DNP) arrays are demonstrated theoretically, supporting the interaction between out-of-plane magnetic plasmons and in-plane lattice resonances, which can be achieved by tuning the nanoparticle height or the array period due to the height-dependent magnetic resonance and the periodicity-dependent lattice resonance. The interplay between the two plasmon modes can lead to a remarkable change in resonance lineshape and an improvement on magnetic field enhancement. Simultaneous electric field and magnetic field enhancement can be obtained in the gap region between neighboring particles at two resonance frequencies as the interplay occurs, which presents “open cavities as electromagnetic field hot spots for potential applications on detection and sensing. The results not only offer an attractive way to tune the optical responses of plasmonic nanostructure, but also provide further insight into the plasmon interactions in periodic nanostructure or metamaterials comprising multiple elements.

Morphology-structure of oriented noncrystalline polyesters has been studied using the parameters changes of the broad peaks in wide angle x-ray scattering (WAXS) with azimuth angles. Two-dimensional WAXS show that the oriented noncrystalline polyester is made up of long plane-like chains arranged in opposition to each other; and these chains are composed of oriented atomic distances with the chain axes parallel to the drawing direction and are closely arranged into lateral ordering. It is concluded that the arrangements of both interchain and intrachain distances are in good order in the oriented direction, while in other directions, they are arranged nearly at random. This shows that the oriented noncrystalline polymers are materials with their ordered structure varying with directions.

The X-ray diffraction pattern of γ-Al 2 O 3 is found to be broadened with every diffraction line being different. This is attributed to the difference of regularity of oxygen ions and aluminium ions. In order to study the structural information shown by this selected broadening, the peak separation processing for the γ-Al 2 O 3 X-ray diffraction pattern has been carried out. It is found that the lattice distortion of γ-Al 2 O 3 can be neglected and the γ-Al 2 O 3 crystallite size is approximately isotropic. Therefore it might be deduced that the selective widening of the diffraction line does not come mainly from the anisotropy of the crystallite shape. According to our result that the diffraction line width with low index (220) is wider than that with high index (440) the selective widening of the diffraction line might come mainly from the structure defect. This implies the possibility of the existence of the stacking fault in the γ-Al 2 O 3 structure and it might be concluded that the diffraction line widening of the γ-Al 2 O 3 caused by the stacking fault leads to the crystalline structure imperfection.

A material with the formula ZrMgMo3O12 having negative thermal expansion is presented and characterized. It is shown that ZrMgMo3O12 crystallizes in an orthorhombic symmetry with space group Pnma(62) or Pna21(33) and exhibits negative thermal expansion in a large temperature range (αl = −3.8 × 10−6 K−1 from 300K to 1000K by x-ray diffraction and αl = −3.73 × 10−6 K−1 from 295K to 775K by dilatometer). ZrMgMo3O12 remains the orthorhombic structure without phase transition or decomposition at least from 123K to 1200K and is not hygroscopic. These properties make it an excellent material with negative thermal expansion for a variety of applications.

Composite nanoparticles (NPs) have the ability of combining materials with different properties together, thus receiving extensive attention in many fields. Here we theoretically investigate the electric field distribution around core/shell NPs (a type of composite NPs) in ferrofluids under the influence of an external magnetic field. The NPs are made of cobalt (ferromagnetic) coated with gold (metallic). Under the influence of the external magnetic field, these NPs will align along the direction of this field, thus forming a chain of NPs. According to Laplace's equations, we obtain electric fields inside and outside the NPs as a function of the incident wavelength by taking into account the mutual interaction between the polarized NPs. Our calculation results show that the electric field distribution is closely related to the resonant incident wavelength, the metallic shell thickness, and the inter-particle distance. These analytical calculations agree well with our numerical simulation results. This kind of field-induced anisotropic soft-matter systems offers the possibility of obtaining an enhanced Raman scattering substrate due to enhanced electric fields.

We theoretically investigate the photonic band gap in one-dimensional photonic crystals with a graded multilayer structure. The proposed structure constitutes an alternating composite layer (metallic nanoparticles embedded in TiO2 film) and an air layer. Regarding the multilayer as a series of capacitance, effective optical properties are derived. The dispersion relation is obtained with the solution of the transfer matrix equation. With a graded structure in the composite layer, numerical results show that the position and width of the photonic band gap can be effectively modulated by varying the number of the graded composite layers, the volume fraction of nanoparticles and the external stimuli.

The errors may be introduced in the process of measurement and evaluation for preparing radial distribution function (RDF), They will cause the error distortion that RDF can be partly upset. RDF method is based on structual isotropy of amor-phous materials, however, a structural anisotropy, i.e orientation, hes been found in amorphous polymeric, inorganic and metallic materials. The orientation will greatly affect RDF, and will lead to a new distortion that RDF may be wholly upset. Obvirously, if it is not given due regard, a misinterpretation on RDF can occur. The feature of the so-called orientation distortion is discussed in the present paper.

Hydrogen is used as a probe for obtaining structural information on TiCu metallic glasses. Resulte from experimental radial distribution functions of hydrided and un- hydrided TiCu glasses show a significant change in the nearest neighbor distance between Ti and Cu atom. The measured distance suggests that hydrogen occupies mainly tetrahedral sites defined by Ti and Cu atoms under following hydriding conditions (85 atm H2–80°C).

In this article the effect of hydrogen on structure of amorphous alloys of the form Ni0.243Zr0.757 Hy 0≤y≤0.25 is reported. The results of investigations on the structure of amorphous Ni0.243Zr0.757 and its hydrogenated sample are described. X-ray diffraction data are employed to calculate their radial distribution functions (RDF(r)) structures. The coordination umber of Ni-Zr metallic glass is determined as 10.6 and the hydrogen atoms in the hydrogenated amorphous Ni0.243Zr0.757H0.25 apparently prefer to occupy the tetrahedral hole surrounded mainly by 4 Zr atoms and a few by 3 Zr + 1 Ni atoms.