Insights into the crystal structure and multifunctional optical properties of A2CdTeO6 (A=Ba, Sr, Ca) double perovskites

Vibrationally Induced Photophysical Response of Sr2NaMg2V3O12:Eu3+ for Dual‐Mode Temperature Sensing and Safety Signs

“…To provide a more detailed analysis, the radiative and nonradiative decay rates at various temperatures were calculated using 4 f –4 f intensity theory. [ 57–65 ] The total radiative decay rate ( A R ) is estimated by taking the sum of radiative rates A 0 J for each 5 D 0 – 7 F J transition given bywhere υ 01 and υ 0 J are frequencies and I 01 and I 0 J are the integrated intensities of the 5 D 0 – 7 F 1 and 5 D 0 – 7 F J transitions and A 01 is the Einstein coefficient between the 5 D 0 and 7 F 1 levels. Using the observed lifetime τ obs of the 5 D 0 level, the nonradiative decay rate, A NR , is calculated by …”

“…At the same time, the almost constant decay time of Eu 3þ implies that a pronounced To provide a more detailed analysis, the radiative and nonradiative decay rates at various temperatures were calculated using 4f-4f intensity theory. [57][58][59][60][61][62][63][64][65] The total radiative decay rate (A R ) is estimated by taking the sum of radiative rates A 0J for each 5 D 0 -7 F J transition given by…”

Role of Ca2+ doping on the enhancement of dielectric properties of Sr2–xCaxNiWO6 for energy storage device application

“…According to the findings, the band gap energy obtained using the Kubelka–Munk relations were closely consistent with those acquired from the Tauc plots which decreased with an increase of Ca 2+ dopant concentration up to x = 0.02. As mentioned by Suraja et al 21 , the band gap energy of double perovskites typically increased as the ionic radius of A-site substituted cations decreased. The octahedral tilting of the double perovskite causes a reduction in the average bond angles which in turn causes a narrowing of the conduction band width.…”

Shedding light on intrinsic characteristics and optical properties of novel selenite and tellurite crystals ZrSe2O6, HfSe2O6 and HfTe3O8

“…[3][4][5] Se 4+ exhibits a tetrahedral SeO 3 coordination, two selenite anions can form dimer (Se 2 O 5 ) 2− via corner-sharing, while Te 4+ can bond with 3, 4 and 5 oxygen atoms forming TeO 3 , TeO 4 and TeO 5 polyhedra, which can form various uncommon structural topologies and diverse Te 4+ oxide clusters, 1D chains, and 2D sheets as well as 3D reticular structures by further interconnecting other unit groups. 6,7 Moreover, Se 4+ and Te 4+ have a one-sided or distorted coordination of ligands owing to the active lone-pair electrons, which can induce second-order Jahn-Teller (SOJT) distortions and the formation of noncentrosymmetric (NCS) or polar structures. 8,9 Meanwhile, it is particularly mentioned here that most transition-metal cations (Cr 3+ , Zr 4+ , Ta 5+ , Hf 4+ , etc.)…”