表征 Ca3WO6 中 [WO6]6- 八面体和 Ca3WO5Cl2 中 [WO5]4- 方锥体的电荷转移发光,Physical Chemistry Chemical Physics

当前位置： X-MOL 学术 › Phys. Chem. Chem. Phys. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

表征 Ca3WO6 中 [WO6]6- 八面体和 Ca3WO5Cl2 中 [WO5]4- 方锥体的电荷转移发光
Physical Chemistry Chemical Physics ( IF 2.9 ) Pub Date : 2022-09-12 , DOI: 10.1039/d2cp02753d
Yuuki Kitagawa ₁ , Shota Takemura ₂ , Daigorou Hirai ₃ , Zenji Hiroi ₃ , Jumpei Ueda ₁ , Setsuhisa Tanabe ₁

Affiliation

不同类型多面体的电荷转移 (CT) 发光，Ca ₃ WO ₅ Cl _{2中的 [WO}₅ ] ^4-和Ca 3 WO 6 中的_[ WO ₆ ] _6-，^通过光谱实验和从头算计算来表征。根据几何优化，W ^{6+离子在Ca}₃ WO ₅ Cl ₂中形成五倍[WO ₅ ] ^4-方锥体，因为W ⁶⁺和Cl ^-之间的原子间距很大。3.266 Å。电子态密度分析揭示了Ca ₃ WO ₅ Cl _2晶格中Cl^-离子对W ⁶⁺离子的离子特性，导致在488 nm处观察到单晶Ca ₃的宽发光带峰WO ₅ Cl ₂样品被分配到 [WO ₅ ] ⁴⁻方形金字塔中的 CT 跃迁。与Ca ₃ WO _6中的[WO₆ ] ⁶⁻八面体相比，[WO ₅ ] ⁴⁻方形金字塔显示出不一致的 CT 能量偏移：更高的 CT 吸收和更低的发光能量。_{由于正交Ca 3} WO ₅ Cl ₂的结构和组成特征，较大的带隙带来更高的吸收能量。假设各向异性[WO ₅ ] ^4-正方锥体的CT态在构型坐标图中偏移较大，解释了Ca ₃ WO ₅ Cl ₂样品热猝灭的红移CT发光带和小活化能比 [WO ₆ ] ⁶⁻八面体。

"点击查看英文标题和摘要"

Characterization of the charge transfer luminescence of the [WO6]6− octahedron in Ca3WO6 and the [WO5]4− square pyramid in Ca3WO5Cl2

Charge transfer (CT) luminescence of different types of polyhedra, [WO₅]⁴⁻ in Ca₃WO₅Cl₂ and [WO₆]⁶⁻ in Ca₃WO₆, is characterized by spectroscopic experiments and ab initio calculations. According to the geometry optimization, W⁶⁺ ions form five-fold [WO₅]⁴⁻ square pyramids in Ca₃WO₅Cl₂ because of a large interatomic distance between W⁶⁺ and Cl⁻ of 3.266 Å. The analysis of the density of electronic states reveals the ionic character of Cl⁻ ions to the W⁶⁺ ions in the Ca₃WO₅Cl₂ lattice, resulting in the observed broad luminescence band peak at 488 nm of the single-crystal Ca₃WO₅Cl₂ sample being assigned to the CT transition in the [WO₅]⁴⁻ square pyramid. Compared with the [WO₆]⁶⁻ octahedron in Ca₃WO₆, the [WO₅]⁴⁻ square pyramid shows an inconsistent CT energy shift: higher CT absorption and lower luminescence energies. The larger bandgap brings about higher absorption energy due to the structural and compositional features of the orthorhombic Ca₃WO₅Cl₂. The redshifted CT luminescence band and small activation energy for the thermal quenching of the Ca₃WO₅Cl₂ sample are explained, assuming that the CT states of the anisotropic [WO₅]⁴⁻ square pyramid take a larger offset in the configurational coordinate diagram than the [WO₆]⁶⁻ octahedron.

更新日期：2022-09-12

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南