ScVO₄: Explorations of Novel Crystalline Inorganic Optical Materials in Rare-Earth Orthovanadate Systems

Abstract

Novel tetragonal scandium orthovanadate crystals doped with neodymium ions (Nd:ScVO4) have been successfully grown with the floating zone (FZ) method for applications in photonic devices. High-temperature stability studies and X-ray structural studies show that thermally induced vanadium oxide vaporization triggers a series of topological transitions from the rutile lattice to the defect fluorite lattice when crystallization begins in the ScVO4 melt. Besides zircon-type ScVO4 and bixbyite-type Sc2O3, a third form with metallic properties called tetragonal Sc2VO5 was thus obtained. Ab initio calculations further reveal that such structural transitions at high-temperature are directly driven by increasing covalency in the scandium−oxygen bonds and are energetically favored. In addition, the anisotropic mechanical and optical properties of ScVO4, such as elastic stiffness, Young’s modulus, dielectric constants, and refractive index, were calculated using density functional theory and evaluated for future applications. The calculated results tend to support the experimental data.

ScVO4under non-hydrostatic compression: a new metastable polymorph

“…For zircon-type ScVO4 we determined Eg = 2.75(5) eV. This band gap is very similar to that of BiVO4 [60] and it is in the middle of the values of Eg predicted for ambient pressure by previous calculations [61] From figure 7 it can be seen that from 0.2 to 7.9 GPa the absorption spectrum only slightly blue shift. From the experiments and calculations we estimated dEg/dP ≈ 1 meV/GPa.…”

Tuning the Bi3+-photoemission color over the entire visible region by manipulating secondary cations modulation in the ScVxP1−xO4:Bi3+ (0 ≤ x ≤ 1) solid solution

“…Noticing in Table 1 reveals that different DFT modeling methods always lead to different Eg values [58-60, 33, 62-66] of ScPO4 and ScVO4. However, as compared to the experimental Eg values [33,[57][58][59][60][61][62][63][64][65][66], the theoretical Eg values from DFT are obviously underestimated. Such scenarios are frequently reported in previous works like in refs.…”

Growth and Characterization of Vanadate Laser Crystals

“…and larger cations such as La 3+ should be paid more attentions, because Sc 3+ has the smallest radius which determines the atypical crystal growing property [26], and La 3+ has the largest radius which induces the dierent crystal symmetry [27].…”