稳定的氧化物 (TbO2和TbO4) 的氧化状态为+IV
Shu-Xian Hu1,2, Xiang Gao2, Wen-Li Zou3
1School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China.
The journal of physical chemistry. A
|July 1, 2025
概括
(terbium) 是已知的的最高氧化状态. 理论研究显示Tb(IV) 在TbO2和TbO4中,Tb 5d轨道对结合至关重要,限制了更高的氧化状态.
科学领域:
- 无机化学 无机化学 有机化学
- 计算化学的计算化学
- 量子化学 是一个量子化学.
背景情况:
- 在历史上,经过实验确认的 (Tb) 的最高氧化状态是Tb (IV).
- 了解高氧化状态化合物的电子结构和结合对于无机化学和材料科学至关重要.
研究的目的:
- 从理论上研究各种分子TbO2和TbO4异构体的相对能量和结构.
- 为了确定这些化合物中Tb和O原子的氧化状态.
- 阐明了限制氧化状态的电子因素.
主要方法:
- 利用了各种Kohn-Sham近似和扩展的合集群方法.
- 采用的多配置基准方法包括RAS/CASPT2和iCIPT2.
- 进行了详细的结合分析,包括轨道贡献.
主要成果:
- 确定了TbO2的基本状态为一个C2v-曲的Tb (IV) 化合物.
- 发现[TbO2]+离子保留Tb(IV),导致一个不寻常的O2基离子 (•O2^3-).
- 确定TbO4的基本状态是与Tb(IV) 的C2v结构,并确定了一个具有Tb(IV) 的竞争性异构体.
- 结合分析显示了Tb 5d轨道对Tb-O结合在Tb (IV) 种中的显著贡献.
- 观察到缺乏明显的Tb 4f-5d杂交,被认为是限制Tb氧化状态的关键因素.
结论:
- 铁 (IV) 被证实是研究的TbO2和TbO4分子中氧化状态最高的.
- 电子结构,特别是Tb 5d轨道的作用和没有显著的4f-5d杂交,决定了Tb (IV) 的稳定性,并防止了更高的氧化状态.
相关概念视频
02:58Properties of Transition Metals
27.3K
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
27.3K
01:26Redox Titration: Other Oxidizing and Reducing Agents
405
Besides iodine, other oxidizing or reducing agents can serve as titrants in redox titrations. Common oxidizing titrants include KMnO4, cerium(IV), and K2Cr2O7. The choice of oxidizing titrants depends on factors like stability, cost, analyte strength, and reaction rate between the analyte and titrant. KMnO4 is a strong oxidizing titrant that reduces from Mn(VII) to Mn(II) in a highly acidic solution, simultaneously oxidizing the analyte to a higher oxidation state. In this case, KMnO4 acts as a...
405
03:14Oxidation Numbers
38.1K
In redox reactions, the transfer of electrons occurs between reacting species. Electron transfer is described by a hypothetical number called the oxidation number (or oxidation state). It represents the effective charge of an atom or element, which is assigned using a set of rules.
38.1K
02:54Coordination Compounds and Nomenclature
22.3K
In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For instance, the four valence electrons of carbon overlap with electrons from four hydrogen atoms to form CH4. The one valence electron leaves sodium and adds to the seven valence electrons of chlorine to form the ionic formula unit NaCl (Figure 1a). Transition metals do not normally bond in this fashion. They primarily form coordinate covalent bonds, a...
22.3K
02:48Ionic Bonding and Electron Transfer
42.4K
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
42.4K
02:42Valence Bond Theory
9.7K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.7K