电子特性和AGOH± (k,m=1-4) 气溶离子集群的碰撞截面
Mohsen Doust Mohammadi1, Somnath Bhowmick1, Anne Maisser1
1Climate & Atmosphere Research Centre, The Cyprus Institute, 20 Konstantinou Kavafi Street, Nicosia 2121, Cyprus. s.bhowmick@cyi.ac.cy.
Physical chemistry chemical physics : PCCP
|May 9, 2024
概括
这项研究预测银氧化 (AgOH) 集群的稳定结构,发现离子集群更具反应性和稳定性. 这些发现支持在集群合成中对氧化金属离子的实验观测.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 在集群合成过程中通过大气压火花剥离观察到氧化金属离子.
- 氧化银氧化物 (AgOH) 集群是在火花消光银 (Ag) 时形成的.
研究的目的:
- 预测AgOH集群的基本状态平衡结构 (k,m = 1-4).
- 研究这些星团内的稳定性和原子间相互作用.
- 计算碰撞截面和预测电流动性,与实验数据进行比较.
主要方法:
- 结合集群与单双 (CCSD) 方法用于结构预测.
- 对稳定能量的计算进行了令人不安的三倍校正.
- 边界分子轨道 (FMO),自然键轨道 (NBO) 和分子中的原子量子理论 (QTAIM) 用于相互作用分析.
- 对碰撞横截面计算的轨迹方法.
主要成果:
- 预测了AgOH集群 (k,m = 1-4) 的地面状态结构,并发现它们是稳定的.
- 与双重或三重状态相比,单一旋转状态表现出更大的分离稳定性.
- 观察到Ag原子 (离子和中性) 对水和基物种的强烈亲和力.
- 阴离子团的反应性更高,并且包含3中心,4电子 (3c/4e) 的超键.
- O-H 键主要是共价的,而 O-Ag 键主要是离子的.
结论:
- 预测的AgOH集群的稳定结构证实了实验发现.
- 阳离子AgOH集群更具反应性,并具有独特的结合特性.
- 计算的电流动性与实验测量结果一致,验证了理论方法.
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