Structure and stability of clusters of β-alanine in the gas phase: importance of the nature of intermolecular interactions.
We present a theoretical study of neutral clusters of β-alanine molecules in the gas phase, (β-ala)nn ≤ 5. Classical molecular dynamics simulations carried out with different internal excitation energies provide information on the clusters formation and their thermal decomposition limits. We also present an assessment study performed with different families of density functionals using the dimer, (β-ala)2, as a benchmark system. The M06-2X functional provides the best agreement in geometries and relative energies in comparison with the reference values computed with the MP2 and CCSD(T) methods. The structure, stability, dissociation energies and vertical ionization potentials of the studied clusters have been investigated using this functional in combination with the 6-311++G(d,p) basis set. An exhaustive analysis of intermolecular interactions is also presented. These results provide new insights into the stability, interaction nature and formation mechanisms of clusters of amino acids in the gas phase.
Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain. dariusz.piekarski@uam.es.
Dariusz Grzegorz
DG
Piekarski
Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain. dariusz.piekarski@uam.es and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain. sergio.diaztendero@uam.es and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Sergio
http://orcid.org/0000-0001-6253-6343
S
Díaz-Tendero
D005740:Gases / Q000737:chemistry*; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D013816:Thermodynamics; D015091:beta-Alanine / Q000737:chemistry*
D005740:Gases; D015091:beta-Alanine