Density-functional theory investigation of electronic structure, elastic properties, optical properties, and lattice dynamics of Ba₂ZnWO₆

Abstract

The electronic structures, optical dielectric functions, elastic properties, and lattice dynamics of Ba 2 ZnWO 6 have been investigated by using the generalized gradient approximation. The density of states and distributions of charge density show that O and Ba tend toward ionic bond, but O and W or Zn display the covalent bond character. The calculated energy band structure shows that Ba 2 ZnWO 6 is a wide indirect band gap semiconductor. The static value 2.28 of the refractive index is attained. The analysis of the elastic properties of Ba 2 ZnWO 6 indicates a rather weak elastic anisotropy. The phonon dispersion is calculated, suggesting no structural instability, which is agreement with the recent low temperature neutron diffraction experiments. The mensurability C v (phonon heat capacity) as the function of the temperature is also calculated to judge our results for future experiment.

An Er3+ doped Ba2MgWO6 double perovskite: a phosphor for low-temperature thermometry

“…3). Due to the indirect bandgap nature of this compound, 4–9 the bandgap energy was extrapolated from the intercept of the fitted straight line at F ( R ) = 0 in the F ( hν ) 1/2 versus the energy ( hν ) plot. The bandgap value is found to be 3.74 eV which is slightly smaller than those of some other double perovskites; for example, La 2 MgTiO 6 :Pr 3+ (3.98 eV) 52 and La 2 MgTiO 6 :Er 3+ (4.07 eV).…”

“…3). Due to the indirect bandgap nature of this compound, [4][5][6][7][8][9] the bandgap energy was extrapolated from the intercept of the fitted straight line at F(R) = 0 in the F(hν) 1/2 versus the energy (hν) plot. The bandgap value is found to be…”

“…Therefore, among others, theoretical investigations using density functional theory have been intensively developed, which show that A 2 BWO 6 and also A 2 BMoO 6 (where A = Ba, Sr and Ca and B = Mg, Zn) are wide bandgap indirect semiconductors. [4][5][6][7][8][9] Furthermore, double-perovskites sometimes are called multifunctional materials because they may exhibit some of these features simultaneously. Moreover, perovskites activated with optical ions possess interesting luminescence properties.…”

Structures, electronic and magnetic properties of transition metal inserted W6O18 clusters

“…The Fermi level is set to be zero [39]. As for pristine W 6 O 18 clusters, the O(p) states contribute to the highest valence band and the W(d) states contribute to the bottom of conduction band [14,25,39,40].…”

Temperature dependence of dielectric and ferroelectric properties for (1−x)Bi0.5(Na0.8K0.2)0.5TiO3-xBaZn0.5W0.5O3lead-free piezoelectric ceramics

“…Moreover, it has been reported that the formation of an MPB region in the BNT-BKT-BiCoO 3 system allows further enhancement of the ferroelectric and piezoelectric properties with respect to the BNT-BKT system [10]. On the other hand, BaZn 0.5 W 0.5 O 3 (BZW), which has a cubic perovskite structure with space group of Fm3m [11] is known to be effective for the enhancement of the piezoelectric properties of Pb-based ceramics [12]. However, the effects of BZW addition on the piezoelectric properties of the BNT-BKT system have not been reported to date.…”