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06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Theoretical investigation on the stability of ionic formic acid clusters
Leonardo Baptista1, Diana P P Andrade, Alexandre Braga Rocha
1Universidade Federal do Rio de Janeiro, Instituto de Quimica, Departamento de Fisico-Quimica, Cidade Universitaria, Ilha do Fundao, 21949-900, Rio de Janeiro, RJ, Brazil. baptista@iq.ufrj.br
The Journal of Physical Chemistry. A
|December 5, 2008
Summary
This study investigates positive charged formic acid clusters formed by fission fragment impacts. Quantum mechanical calculations reveal that cluster stability decreases with size, with hydrogen atom migration crucial for structural integrity.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Positive charged formic acid clusters are formed by (252)Cf fission fragments impacting icy targets.
- Understanding cluster formation and stability is crucial for various chemical and physical processes.
Purpose of the Study:
- To investigate the structures and stability of formic acid clusters, (HCOOH)(n)H(+) and (HCOOH)(n)H(3)O+, where 2 ≤ n ≤ 4.
- To elucidate the mechanisms underlying cluster stability through computational analysis.
Main Methods:
- Ab initio electronic structure calculations were employed to determine cluster structures.
- Stability analysis incorporated electronic energy, zero-point vibrational energy correction, and basis set superposition error (BSSE) correction.
- Born-Oppenheimer molecular dynamics simulations were used to evaluate temporal behavior and stability mechanisms.
Main Results:
- Proposed structures for formic acid clusters (n=2-4) were identified.
- Cluster growth did not follow a regular nucleation pattern.
- Stability analysis indicated a decay in stability with increasing cluster mass, consistent with experimental observations.
- Hydrogen atom migration between formic acid moieties was identified as a key mechanism for maintaining structural stability.
Conclusions:
- The study provides insights into the non-regular growth patterns of formic acid clusters.
- Computational findings align with experimental observations regarding cluster stability.
- Hydrogen atom migration plays a vital role in stabilizing these charged molecular clusters.
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