UVC Up-Conversion and Vis-NIR Luminescence Examined in SrO-CaO-MgO-SiO Glasses Doped with Pr.

The application of ultraviolet-C light in the field of surface treatment or photodynamic therapy is highly prospective. In this regard, the stable fluorescent silicate SrO-CaO-MgO-SiO-PrO glasses able to effectively convert visible excitation on the ultraviolet praseodymium emission were fabricated and examined. An unusual wide-range visible-to-UVC up-conversion within 240-410 nm has been achieved in Pr-doped glasses, revealing their potential advantage in different sophisticated disinfection technologies.

Upconversion Luminescence Properties of Pr-Doped BaYF Nanoparticles Prepared by Microwave Hydrothermal Method.

Pure and Pr-doped BaYF nanoparticles were synthesized by the microwave hydrothermal method. The nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and optical spectroscopy. The XRD and TEM confirm that the average size of nanoparticles is in the range of 26-37 nm.

Exploring Structure-Sensitive Factors Relevant to Cryogenic Laser Operation in Oxide Crystals Doped with Er Ions.

Crystals of GdAlGaO:Er, (LuGd)SiO:Er and LiNbO:Er compounds differing in origin and the nature of their inherent structural disorder were crystalized. Optical absorption and luminescence spectra for transitions between the I and the I multiplets of Er ions for the crystal samples were recorded versus temperatures in the region of 80-300 K. Gathered data were analyzed thoroughly providing the in-depth knowledge of the effects of temperature on intensities, wavelengths and bandwidths of Er transitions.

Synthesis and Characterization of LiMgGeO:Ho.

In this work, the synthesis and characterization of LiMgGeO:Ho ceramics were reported. The X-ray diffraction measurements revealed that the studied ceramics belong to the monoclinic LiMgGeO. Luminescence properties were analyzed in the visible spectral range.

Exploring the Impact of Structure-Sensitivity Factors on Thermographic Properties of Dy-Doped Oxide Crystals.

Optical absorption spectra and luminescence spectra were recorded as a function of temperature between 295 K and 800 K for single crystal samples of GdSiO:Dy, LuSiO:Dy, LiNbO:Dy, and GdGaAlO:Dy fabricated by the Czochralski method and of YAl(BO):Dy fabricated by the top-seeded high temperature solution method. A thermally induced change of fluorescence intensity ratio (FIR) between the I→ H and F → H emission bands of Dy was inferred from experimental data. It was found that relative thermal sensitivities S at 350 K are higher for YAl(BO):Dy and LuSiO:Dythan those for the remaining systems studied.

Temperature- and pressure-induced phase transitions in the metal formate framework of [ND₄][Zn(DCOO)₃] and [NH₄][Zn(HCOO)₃].

Vibrational properties and the temperature-induced phase transition mechanism have been studied in [NH4][Zn(HCOO)3] and [ND4][Zn(DCOO)3] metal organic frameworks by variable-temperature dielectric, IR, and Raman measurements. DFT calculations allowed proposing the detailed assignment of vibrational modes to respective motions of atoms in the unit cell. Temperature-dependent studies reveal a very weak isotopic effect on the phase transition temperature and confirm that ordering of ammonium cations plays a major role in the mechanism of the phase transition.

Perovskite metal formate framework of [NH2-CH(+)-NH2]Mn(HCOO)3]: phase transition, magnetic, dielectric, and phonon properties.

We report the synthesis, crystal structure, and thermal, dielectric, phonon, and magnetic properties of [NH2-CH(+)-NH2][Mn(HCOO)3] (FMDMn). The anionic framework of [(Mn(HCOO)3(-)] is counterbalanced by formamidinium (FMD(+)) cations located in the cavities of the framework. These cations form extensive N-H···O hydrogen bonding with the framework.

Structure, phonon properties, and order-disorder transition in the metal formate framework of [NH4][Mg(HCOO)3].

We report the synthesis, crystal structure, thermal, dielectric, IR, and Raman studies of [NH4][Mg(HCOO)3] formate. Single-crystal X-ray diffraction shows that it crystallizes in the hexagonal space group P6322, with orientationally disordered NH4(+) ions located in the cages of the network. Upon cooling, [NH4][Mg(HCOO)3] undergoes a phase transition at around 255 K to the ferroelectric P63 structure.

Order-disorder transition and weak ferromagnetism in the perovskite metal formate frameworks of [(CH3)2NH2][M(HCOO)3] and [(CH3)2ND2][M(HCOO)3] (M = Ni, Mn).

We report the synthesis, crystal structure, thermal, dielectric, Raman, infrared, and magnetic properties of hydrogen and deuterated divalent metal formates, [(CH3)2NH2][M(HCOO)3] and [(CH3)2ND2][M(HCOO)3], where M = Ni, Mn. On the basis of Raman and IR data, assignment of the observed modes to respective vibrations of atoms is proposed. The thermal studies show that for the Ni compounds deuteration leads to a decrease of the phase transition temperature Tc by 5.