We present a systematic investigation of the depolarization properties of a supercontinuum accompanied with femtosecond laser filamentation in barium fluoride (BaF2) crystal. It is found that the depolarization of the supercontinuum depends strongly on the crystal orientations with respect to the incident laser polarization. At most crystal orientations, the depolarization of the supercontinuum rises with the increase of the input laser energies and finally saturates. While at 45°, the depolarization of the supercontinuum is not changed and keeps nearly negligible with the increase of the input laser energies. These peculiar depolarization properties of the supercontinuum can be ascribed to the orientation dependence of the cross-polarized wave (XPW) generation and ionization-induced plasma scattering in the BaF2 crystal.

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Herein, we report six neutral Cu(I) halide complexes based on [CuX(BIM)(P^P)] (P^P, diphosphine ligands; BIM, 1-butylimmidazole) with intense blue emission. When diphosphine ligands (POP, bis(2-(diphenylphosphino)phenyl)ether; Xantphos (4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)), BIM and CuX (X = I, Br, Cl) were mixed in solution, pure and high yield products were obtained. Single crystal X-ray diffraction showed that each complex was of copper-centered tetrahedral structure. Different weak interactions in the molecules, such as hydrogen bonds, π−π stacking, and C−H•••π, make them exhibit various stacking modes like 1D, 2D, or 3D. Photoluminescent spectra showed various emissions from 444 to 480 nm with excellent quantum yields from 38.8% (6) to 92.3% (2). Interestingly, after heating complex 1-CH 2 Cl 2 at 60 °C, the emission exhibited a hypochromatic shift to 458 nm from the original 470 nm at room temperature. Complex 4-CH 2 Cl 2 showed an opposite bathochromic shift from 444 to 470 nm. Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) characterizations illustrated that the emission change was the result of the solvent (CH 2 Cl 2 ) loss from the pores of the structures. While they were put under a dichloromethane atmosphere, they demonstrate reversible luminescence reduction. Further research was carried out to prove the effect of pore solvent on terminal luminescence by synthesizing complex 4-THF (tetrahydrofuran). It showed a similar structure as complex 4-CH 2 Cl 2 but with different emission at 472 nm. Terahertz (THz) time domain spectra were applied to explore the relationship between structure and emission. After heating, the spectrum of complex 4-CH 2 Cl 2 changed a lot compared to the original and was dramatically similar to 4-THF. This inviting discovery suggests that the loss of solvent promotes the conversion of complex 4-CH 2 Cl 2 to a new crystal phase, which is more closed to 4-THF. THz technology provides a new measure to analyze molecules, especially for materials without crystal structure information.

Five novel mononuclear [Cu(Bphen)(bdppmapy)]X complexes showing photoluminescence were synthesized. The same diphosphine ligand and diimine ligand and different Cu(I) salts were used in the one-pot synthesis of complexes 1-5. These...

Herein, a series of ionic mononuclear Cu(I) complexes, [Cu(phen)(bdppmapy)]Cl (1a), [Cu(phen)(bdppmapy)]Br (2a), [Cu(phen)(bdppmapy)]I (3a), [Cu(phen)(bdppmapy)]SCN (4a), [Cu(Dpq)(bdppmapy)]Cl (1b), [Cu(Dpq)(bdppmapy)]Br (2b), [Cu(Dpq)(bdppmapy)]I (3b) and [Cu(Dpq)(bdppmapy)]SCN (4b) {phen = [1,10]phenanthroline; Dpq =...