电子结构研究的YNbTiO[公式:见文本]和CaNb[公式:见文本]O[公式:见文本]与使用化合物调节嵌入潜力方法的活性化物杂质
Daniil Maltsev1, Yuriy Lomachuk2, Vera Shakhova2
1Petersburg Nuclear Physics Institute named by B.P. Konstantinov of National Research Center "Kurchatov Institute" (NRC "Kurchatov Institute" - PNPI), mkr. Orlova roscha, 1, Leningrad district, 188300, Gatchina, Russian Federation. malcev_da@pnpi.nrcki.ru.
Scientific reports
|March 28, 2025
概括
化合物调节嵌入潜力 (CTEP) 方法模拟了酸盐晶体中的活性化物替代,揭示了由于电子转移而发生的氧化状态变化. 这项研究增强了对复杂材料中活性化物行为的理解.
科学领域:
- 计算材料科学科学 计算材料科学
- 固态化学 固态化学
- 核材料 核材料 核材料
背景情况:
- 在核废物管理和材料科学中,将乙化物纳入晶体结构至关重要.
- 由于其复杂的电子配置,理解行为替代的局部结构和电子效应是具有挑战性的.
研究的目的:
- 在YNbTiO[公式:见文本]和CaNb[公式:见文本]O[公式:见文本]中使用化合物调节式嵌入潜力 (CTEP) 方法来研究actinide (U,Np,Pu,Am,Cm) 替代.
- 分析替代物对局部结构,氧化状态和电子性质的影响.
- 探索使用CTEP模拟无序的阴离子分布.
主要方法:
- 应用复合调节嵌入潜力 (CTEP) 方法用于集群计算.
- 几何放松和分析旋转密度分布和X射线辐射光谱的化学转移.
- 利用单中心和多中心集群模型,包括为替代品提供收费补偿空缺.
- 模拟的TiNb替代物用于模拟阴离子乱.
主要成果:
- 动氨酸替代通常会导致类似的局部结构扭曲,但在高氧化状态下的Am,Cm和Pu发生了电子转移,减少了它们的氧化状态.
- 替代表现出复杂的行为:U[公式:查看文本]氧化状态下降,而U[公式:查看文本]增加到U[公式:查看文本].
- 在CTEP模拟中,有效地模拟了阴离子乱 (TiNb) 对结构性和电子性质的影响,与特殊类随机结构 (SQS) 方法相比.
结论:
- 该CTEP方法提供了有价值的洞察力,在niobate晶体结构内,对actinide行为和氧化状态的演变.
- 电子转移机制显著影响着活性化物的最终氧化状态,特别是Pu,Am和Cm.
- CTEP是一种可行的方法,用于模拟复杂的现象,如材料中的行为替代和阴离子乱.
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