对Sn2+,Pb2+和Hg2+异常酸度的分子图
1School of Chemistry, Physics and Environmental Science, University of Sussex, Falmer, Brighton BN1 9QJ, United Kingdom.
Journal of the American Chemical Society
|March 25, 2004
概括
锡,和二离子很容易与水进行质子转移. 这种在气体和凝结阶段观察到的轻易反应与二相反,突出显示出独特的化学特性.
科学领域:
- 无机化学 无机化学
- 物理化学 物理化学
- 计算化学计算化学
背景情况:
- 已知锡 (Sn2+), (Pb2+) 和 (Hg2+) 的二离子与水相互作用.
- 了解这些金属离子在水环境中的行为对于各种化学和生物过程至关重要.
研究的目的:
- 为了研究Sn(2+),Pb(2+) 和Hg(2+) 和水之间的质子转移反应.
- 用计算方法阐明反应机制和涉及的能量障碍.
- 为了比较这些二酸盐与 (Ca2+)) 的反应活性,作为参考.
主要方法:
- 在冷凝和气态阶段进行实验研究.
- Ab initio计算以确定结构和质子转移反应概况.
- 对M = Sn,Pb,Hg和Ca的复合物[M.
主要成果:
- Sn2+),Pb2+和Hg2+) 与水容易发生质子转移,导致气相中的水解产物.
- 计算显示,水分子的运动构成了Sn{2+},Pb{2+}和Hg{2+}中质子转移的主要障碍.
- (Ca2+)) 在质子转移步骤中表现出显著的障碍,与其他研究的二不同.
结论:
- 与水的质子转移反应对于Sn{2+},Pb{2+}和Hg{2+}来说很容易,这是由于水的流动性,惰性单独对和共价键等因素.
- 在Sn(2+) 和Pb(2+) 中的惰性单一对影响复杂的几何形状,有助于质子转移.
- Hg(2+) 的质子转移是由其相互作用中的显著共价性特征促进的.
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