在三坐标和的非平面性:X3Hn(m) (X = B,Al,Ga) 的循环结构
Gantasala N Srinivas1, Anakuthil Anoop, Eluvathingal D Jemmis
1Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
理论研究表明, (B) 的结构与X3Hn物种中的 (Al) 和 (Ga) 等较重元素有显著差异. 对于Al和Ga化物来说,重原子上的非平面排列和单独对是常见的.
科学领域:
- 计算化学是一种计算化学.
- 无机化学 无机化学 无机化学
- 理论化学是一种理论化学.
背景情况:
- 研究阳离子,中性和阴离子X3Hn物种的结构和能量对于理解化学键和反应性至关重要.
- 之前的研究往往集中在更轻的元素上,使更重的13组元素的行为不那么被探索.
研究的目的:
- 理论上研究X3H3(2-),X3H4-,X3H5和X3H6+的结构和能量,因为X= (B), (Al) 和 (Ga).
- 为了比较这些要素之间的结构偏好和稳定趋势.
- 在较重的13组化物中识别新的结构动图和结合特性.
主要方法:
- 密度函数理论 (DFT) 计算使用B3LYP函数与6-311G(d) 基础集.
- 全球和局部结构搜索以确定潜在能量表面的最小值.
- 使用同位体方程计算共振稳定能量 (RSE).
主要成果:
- (B) 的全球最小结构不是 (Al) 和 (Ga) 的全球最小结构.
- 与 (B) 相比,较重的元素 (Al,Ga) 呈现出较多的最小值 (X3H3(2-),X3H4-,X3H5 的最小值分别为7,6,8)
- 不平面的排列和单双对重原子的主导地位在Al和Ga物种中普遍存在. 在X3H4-(2g) 中观察到Al和Ga的三坐标金字塔排列.
- 对于Al和Ga,pi-移位的影响从X3H3(2-) 减少到X3H6+
结论:
- X3Hn物种的结构景观在 (B) 和更重的元素 (Al,Ga) 之间有显著的分歧.
- 对X3H3(2-) 极小的质子化为X3H4-,X3H5和X3H6+提供了一条产生最小能量结构的途径.
- 该研究揭示了Al和Ga化物中独特的结合和结构特征,挑战了传统的化学直觉.
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