Structure, Morphology, and Spectroscopy Studies of La1−xRExVO4 Nanoparticles Synthesized by Various Methods

Structure and spectroscopy characterization of La1-xSmxVO4 luminescent nanoparticles synthesized co-precipitation and sol-gel methods

“…The V atoms are coordinated by four equivalent oxygen atoms forming the perfect VO 4 tetrahedrons with T d local symmetry of oxygen surrounding. The La atoms are coordinated by eight oxygen atoms with identical four short bond lengths and four long bond lengths with D 2d local symmetry of oxygen surrounding [37,48]. At monoclinic crystal structure, the V and La atoms are fourand nine-fold coordinated, respectively, with C s local symmetry of oxygen surrounding for the both cations.…”

“…3− vanadate anion. The peaks at 440 cm −1 and stronger wide band in the range 700-1000 cm −1 with peaks around 800 cm −1 should be assigned, respectively, to ν 4 and ν 3 vibration modes of the VO 4 3− anion [37][38][39]. The IR absorption of nanoparticles synthesized by different methods is characterized by some spectral differences.…”

“…The ν 3 stretching vibration mode of the VO 4 3group is triple degenerated. It is not split in the spectra of the samples containing VO 4 3groups of tetrahedral symmetry (tetragonal crystal lattice, nanoparticles synthesized by co-precipitation) and it is split on three components in the spectra of the samples containing VO 4 3groups of lowered symmetry (C s symmetry, monoclinic crystal lattice) [37,48].…”

Luminescent Spectroscopy of the Yb3+Ions in the PbWO4Crystal

“…Luminescent measurements under UV excitation were carried out using synchrotron radiation at SUPERLUMI station at HASYLAB, Hamburg, Germany as it was described in [25,26]. Excitation spectra of the IR luminescence were measured at R&D Laboratory "Spectroscopy of condensed state of matter" (Physics Faculty of the Taras Shevchenko National University of Kyiv) using radiation of power xenon lamp [27].…”