Issue 45, 2018

Ab initio molecular dynamics study of solvated electrons in methanol clusters

Abstract

We performed a series of ab initio molecular dynamics simulations to investigate the physical properties of small methanol cluster anions, [(CH3OH)n], (n = 8–32). An excess electron was attached to neutral clusters that were prepared to accommodate the electron in interior cavity states or surface bound states. The computed initial binding energies of the electrons to these clusters indicate appealing similarity to the experimentally observed vertical detachment energies. The tendency of the interior state clusters parallels that of the clusters with strong electron binding in the experiments, while the simulated unrelaxed surface state anions are similar to the observed weakly bound species. This assignment is consistent with a previous identification based on hybrid quantum-classical simulations. The time evolution of the cluster anions suggests that interior state electrons slowly move to and relax on the surface, in excess electronic states that appear significantly more stable than the experimentally assigned putative surface states. Based on this result we predict the existence of relaxed surface state isomers of small methanol cluster anions. Due to the kinetic metastability of the experimentally found weakly bound species, we anticipate a serious technical challenge to prepare and identify small methanol cluster anions with relaxed surface states. These more strongly binding surface states are stabilized by dangling hydroxyl hydrogen atoms pointing to the excess electron's charge distribution. In addition, methyl hydrogens also appear to contribute to the stability of these states. During its transition to the surface, the interior excess electron maintains its initial solvent cavity. No signs of non-cavity interior states are observed in the present first principles ab initio molecular dynamics simulations.

Graphical abstract: Ab initio molecular dynamics study of solvated electrons in methanol clusters

Supplementary files

Article information

Article type
Paper
Submitted
08 Aug 2018
Accepted
23 Oct 2018
First published
24 Oct 2018

Phys. Chem. Chem. Phys., 2018,20, 28741-28750

Ab initio molecular dynamics study of solvated electrons in methanol clusters

L. Mones, G. Pohl and L. Turi, Phys. Chem. Chem. Phys., 2018, 20, 28741 DOI: 10.1039/C8CP05052J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements