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We report on the synthesis of two acentric and one centrosymmetric Zn metal–organic complexes with 3-tetrazolemethyl pyridine spacers obtained in situ by hydrothermal routes. X-ray diffraction structural analysis reveals that they have the same equivalent nodes but with dissimilar topologies. The two acentric frameworks [Zn(Tzmp)Cl]n (1) and ([Zn(Tzmp)Br]n (2), HTzmp = 3-tetrazolemethyl pyridine) are isomorphism which exhibit an acentric 3D framework with (10, 3)-b net called “ths”, while the centrosymmetric complex ([Zn(Tzmp)N3]n (3)) features a distinctive 2D sheet with Shubnikov hexagonal plane net. Photo-luminescent studies suggest the ligand-field strength of coordinated negative ions (Cl− > Br− > N3−) has ordered adjusting effects on the emission redshift. The second harmonic generation (SHG) measurement shows that compounds 1 and 2 are nonlinear optically active, with SHG responses being 2/3 and half of the standard potassium dihydrogen phosphate (KDP), respectively.

Reversible crystal state structural phase transitions molecular materials without metal have been received increasing interest recently. Here we successfully synthesized a novel ternary neutral co-crystallized organic adduct hexamethylenetetramine·1-adamantane carboxylic acid·chloroform, 1, which accompanies with an interesting reversible phase transition close to the zero temperature (263 K). We confirmed this reversible phase transition by its switchable thermal dielectric behaviors and unit cell constants anomalies around the phase transition temperature (Tc). X-ray single crystal diffraction analysis above (1-RTP) and below (1-LTP) Tc suggests that the order-disorder motion from the adamantane ring in 1-adamantane carboxylic acid triggered the reversible phase transition.

We experimentally study intracavity four-wave mixing (FWM) using Λ -type, three-level electromagnetically induced transparency (EIT) atoms confined in an optical ring cavity. The original dark-state peak disappears accompanying the generation of intracavity FWM when the coupling light is changed from traveling-wave to standing wave. Additionally, this FWM signal is on resonance with the optical cavity only when the coupling laser is detuned from the atomic resonance center, where the absorption is drastically reduced for both the probe and FWM fields. At last, we do theoretically analysis for the susceptibility of this composite atom–cavity system.

Herein, the crystallization behavior, thermal stability, phase composition, and magnetic properties of Co66.5Si15.5B12Fe4Ni2 amorphous alloy were determined via differential scanning calorimetry, X-ray diffraction analysis, and vibrating sample magnetometry. The heating rate was found to strongly affect the glass-transition and crystallization behavior of Co66.5Si15.5B12Fe4Ni2 solidified ribbon. Based on the crystallization behavior, the relationship between the glass-transition temperature (Tg) and the heating rate (lnβ) was derived as Tg = 6lnβ + 709 and the glass-transition activation energy, initial crystallization activation energy, first crystallization peak activation energy, and the second crystallization peak activation energy were also calculated. Based on the results, the nucleation mechanism of the crystallization of Co66.5Si15.5B12Fe4Ni2 amorphous alloy and the crystallization products of the annealing crystallization process were discussed. The phase composition after short-term annealing at a low temperature was found to be β-Co + α-Co + Ni3Fe + Ni4B + Ni2Si. Following high-temperature, long-term annealing, Ni2Si disappeared completely and a new phase, FeSi, was formed. By studying the coercivity, remanence, saturation magnetization, and magnetic anisotropy of the alloy, we obtained the best processing parameters for comprehensive soft magnetic properties. The results provide guidance on the development of new soft magnetic materials.

The effects of WO 3 addition on the electromagnetic properties of NiCuZn ferrite prepared by usual ceramic technology were investigated. Experimental results show that the substitution of W 6+ ions in NiCuZn ferrite can improve not only electromagnetic properties but also microstructures of sintered ceramic. Along with the reduction of average grain size, pores at grain boundaries decrease with the increasing WO 3 contents. The real part of complex permittivity e ′ and the bulk density increase with the increasing amount of W 6+ ions. Meanwhile, the resonance frequency increases on the condition of deterioration of the real part of complex permeability μ ′ .