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We report that the tail modulation of Stokes pulses in the high-energy stimulated Brillouin scattering pulse compression can be suppressed by controlling effective pulse width of the pump. It is shown through numerical simulations and validated experimentally that the effective pulse width is an appropriate parameter, which determines the generation of tail modulation. The effective pulse width broaden as the increase of energy. This mechanism leads to the amplification of Stokes tail edge and it is the cause of tail modulation.

Based on azabicyclo ligands, four 3D supramolecular lanthanide complexes have been synthesized through hydro(solvo)thermal reactions, generally formulated as [Dy(bipy) (NO3)3]2 (1·Dy), [Dy(bipy)2(NO3)3] (2·Dy), [Dy2(bpdc)3(DMF)(H2O)]2·(DMF)10(H2O) (3·Dy) and [Eu4(bpdc)6(CH3NH2)3(DMSO)(H2O)] (4·Eu) (Bipy = 2,2′-bipyridine; H2bpdc = 2,2′-bipyridine-5,5′-dicarboxylic acid, DMF = N,N-dimethylformamide), and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and powder X-ray diffraction (PXRD). There are three kinds of hydrogen bonding, C2–H2A⋯O6, C4–H4A⋯O4 and C8–H8A⋯O8 along the a/c, b, c axis, respectively in complex 1·Dy. They connect the 1·Dy complex into a 3D 6-connected pcu supramolecular network. 2·Dy is connected into a 3D network with 8–connected bcu architecture by two kinds of hydrogen bonding: C2–H2A⋯O1 and C9–H9A⋯O3. In order to connect the polymer to form a 3D complex, H2bpdc has been chosen in the synthesis and design of the crystal. In the network of 3·Dy, two kinds of Dy(III) cations in different coordination models construct the different binuclear [Dy2O14(DMF)2] and [Dy2O12(H2O)2], and further form the (4,4,6)-connected 3D architecture. The isostructural complex 4·Eu has been synthesised simultaneously. The property of luminescence in solid state or different solvents of the four complexes has been studied in detail. The four complexes show the unique emission peaks of lanthanide cations. Futhermore, in 3·Dy and 4·Eu, the ligand shows a rare bimodal emission, which can sensitize the emission of europium cations as an “antenna effect”, and the shorter one keeps its blue emission though coordinated with Dy(III) cations. Based on the synthesis of green or red color materials, multicolored photoluminescence tuning has been studied in detail through growth of a series of bimetallic complexes, the crystal formula as [Dy2nEu′2−2n(bpdc)3(DMF)(H2O)] (M-1–M-9; 0 < n < 1). We achieved dichromatic fine-tuning among the triangle region of red, green and white. The linear dependence of the emissions has been analyzed, and the mathematical matrix model is useful to calculate the ratio and excitation wavelength for a given color in need.

We design two novel d10 metal complexes [Zn(3-qlc)2]n (Zn1), [Cd(3-qlc)2]n (Cd1) (3-Hqlc = quinoline-3-carboxylic acid), which display similar 2D layer structures, and further form 3D 6-connected primitive cubic (pcu) network topology via π⋯π stacking interactions with the point symbol {412·63}. Complexes Zn1 and Cd1 exhibit tunable luminescence and photovoltaic properties as a new type of multifunctional materials. Zn1 and Cd1 show tunable luminescence from blue to green by varying the temperature in the solid state. What's more, both of them exhibit excellent aggregation-induced emission (AIE) properties in DMSO/water mixtures. Encouraged by the UV-visible absorption in an ethanol solution result, Zn1 and Cd1 can be considered as co-sensitizers in combination with N719 to investigate their effect on enhancing the dye-sensitized solar cells (DSSCs) performance. Zn1 and Cd1 could overcome the deficiency in the ruthenium complex N719 absorption in the ultraviolet and blue-violet region, offsetting competitive visible light absorption of I3− and reducing the charge recombination of injected electrons. After being co-sensitized with Zn1 and Cd1, the devices co-sensitized by Zn1/N719 and Cd1/N719 yield an overall efficiency of 7.75% and 7.70%, which are 44.59% and 43.66% higher than that of the device sensitized only by N719 (5.36%).

A method of generating flat-top waveform in the time-domain based on stimulated Brillouin scattering (SBS) using medium with short phonon lifetime is proposed. In theory, the transmitted pulse is simulated in the case of several media with different phonon lifetime. In experiment, FC-72 and HT-270, which differ significantly in the phonon lifetime, are exploited in the experiment. Both the theoretical and experimental results indicate that, when choosing medium with short phonon lifetime, the top is almost a platform, while there is a peak in the front and a platform thereafter when choosing medium with long phonon lifetime.

In the title centrosymmetric dinuclear complex, [Eu(2)(CH(3)CO(2))(6)(C(12)H(8)N(2))(2)], the Eu(III) atom is nine-coordinated by two N atoms from a 1,10-phenanthroline ligand and seven O atoms from five acetate ligands (two bidentate, three monodentate). The crystal structure is stabilized by π-π stacking inter-actions between the pyridine and benzene rings of adjacent mol-ecules, with a centroid-centroid distance of 3.829 (2) Å.