在Ag(n) V(+) 集群中的价值转换和旋转矩的性质
Victor M Medel1, Arthur C Reber, Vikas Chauhan
1Department of Physics, Virginia Commonwealth University , Richmond, Virginia 23284-2000, United States.
Journal of the American Chemical Society
|May 15, 2014
概括
银 (Ag-V) 集群表现出独特的电子结构和稳定性. 由于超原子轨道外的关闭,特定数量的银原子 (5,7和14) 会导致高度稳定的阴离子团.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
背景情况:
- 了解小金属集群的电子结构和稳定性对于设计新材料至关重要.
- 由于其独特的电子和磁性特性,银- (Ag-V) 星团引起了人们的兴趣.
研究的目的:
- 为了研究原子结构的演变,结合,稳定性和中性和阴性Ag-V集群中的自旋磁矩.
- 确定控制这些星团稳定的因素,特别是超原子轨道和的价值变化的作用.
主要方法:
- 第一个原则密度函数理论 (DFT) 计算.
- 使用梯度校正的函数来准确确定电子结构.
- 分析原子结构,结合特性和自旋磁矩.
主要成果:
- 在小尺寸时,的4s状态与银状态混合,形成超原子轨道,而3d状态保持局部化,使的有效价值为1或2.
- 从Ag8V(+) 开始,的3D状态参与了结合,使其有效价值增加到5并形成1D超原子轨道.
- 对于具有5,7和14个银原子的阴离子集群,观察到三种不同的外关闭,表明其高稳定性,这与充满的1S,1P和1D超原子外相对应.
结论:
- 阴离子Ag-V集群的稳定性是由超原子电子 (1S,1P,1D) 的填充决定的.
- 在这些集群中,的有效价值因尺寸和电子外填充而显著变化.
- 理论预测与从质谱数据中对集群稳定的实验观测一致.
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