Vibrational dynamics of single-crystal YVO4studied by polarized micro-Raman spectroscopy andab initiocalculations

Abstract

The vibrational properties of yttrium orthovanadate (YVO 4) single crystals, with tetragonal zircon structure, have been investigated by means of polarized micro-Raman spectroscopy and ab initio calculations. Raman spectra were taken at different polarizations and orientations carefully set by the use of a micromanipulator, so that all of the twelve Raman-active modes, expected on the basis of the group theory, were selected in turn and definitively assigned in wave number and symmetry. In particular the E g (4) mode, assigned incorrectly in previous literature, has been observed at 387 cm −1. Moreover, the very weak E g (1) mode, peaked at about 137 cm −1 , was clearly observed only under some excitation wavelengths, and its peculiar Raman excitation profile was measured within a wide region of the visible. Finally, ab initio calculations based on density-functional theory have been performed in order to determine both Raman and infrared vibrational modes and to corroborate the experimental results. The rather good agreement between computational and experimental frequencies is slightly better than in previous computational works and supports our experimental symmetry assignments.

High-pressure polymorphs of TbVO4: A Raman and ab initio study

“…These modes, and especially the two translational modes, are also absent in most of the Raman scattering measurements performed in other orthovanadates probably due to their weak Raman scattering cross-section [37,38]. Curiously, they have been found recently in polarized Raman measurements in YVO 4 at ambient pressure [39]. [14].…”

Recent progress on the characterization of the high-pressure behaviour of AVO4 orthovanadates

“…We will start with the zircon-type structure. Different authors have performed a detailed group-theoretical analysis of phonons in the zircon-type structure [66,77]. In order to describe this structure a primitive cell can be chosen with only two formula units.…”

Structural, luminescence and thermometric properties of nanocrystalline YVO4:Dy3+ temperature and concentration series

“…The external vibration at 157 cm −1 (B 1g (1)) can be attributed to the O–Y–O bending mode. The internal vibrations, which can be ascribed to the O–V–O bending and VO 4 stretching modes, are located at higher frequencies: 259 (B 2g ), 376 (A 1g (1)), 488 (B 1g (3)), 812 (B 1g (4)), 835 (E g (5)) and 888 cm −1 (A 1g (2)) 43 . The observed spectrum is dominated by the totally symmetrical vibration of VO 4 3− tetrahedron 32 .…”