Universidade Estadual do Rio de Janeiro, Faculdade de Tecnologia, Departamento de Quimica e Ambiental, Rodovia Presidente Dutra Km 298, Resende, RJ, Brazil.
J Phys Chem A. 2010 Jul 8;114(26):6917-26. doi: 10.1021/jp100425h.
Recent experimental results on negatively charged formic acid clusters generated by the impact of (252)Cf fission fragments on icy formic acid target are compared to quantum mechanical calculations. Structures for the clusters series, (HCOOH)nOH(-), where 2 < or = n < or = 4, are proposed based on ab initio electronic structure methods. The results show that cluster growth does not have a regular pattern of nucleation. A stability analysis was performed considering the commonly defined stability function. Temporal behavior of the clusters was evaluated by Born-Oppenheimer molecular dynamics to check the mechanism that provides cluster stability. The evaluated temporal profiles indicate the importance of hydrogen atom migration between the formic acid moieties in maintaining the stability of the structures and the water formation due to hydrogen abstraction by the hydroxyl approach.
最近关于（252）Cf 裂变碎片撞击冰甲酸靶产生带负电荷的甲酸团簇的实验结果与量子力学计算进行了比较。基于从头算电子结构方法，提出了团簇系列（HCOOH）nOH（-）（其中 2 < n < 4）的结构。结果表明，团簇的生长没有核化的规则模式。通过 Born-Oppenheimer 分子动力学考虑常用的稳定性函数对稳定性进行了分析。通过评估团簇的时间行为来检查提供团簇稳定性的机制。评估的时间曲线表明，甲酸部分之间的氢原子迁移在维持结构稳定性和由于羟基接近而导致的水形成方面的重要性。
