Issue 23, 2007

Perturbation of water structure due to monovalent ions in solution

Abstract

The ion induced modification to the tetrahedral structure of water is a topic of much current interest. We address this question by interpreting neutron diffraction data from monovalent ionic solutions of NaCl and KCl using a computer assisted structural modeling technique. We investigate the effect that these ions have on the water–water O–O, O–H and H–H radial distribution functions as a function of ionic concentration. It is found that the O–H and H–H functions are only marginally affected by ionic composition, signaling that hydrogen bonding between water molecules remains largely intact, even at the highest concentrations. On the other hand the O–O functions are strongly modified by the ions. In particular the position of the second peak in gOO(r), is found to move inwards with increasing salt concentration, in a manner closely analogous to what happens in pure water under pressure. Furthermore by recalculating gOO(r) after excluding all the water molecules in the first hydration shell of each ion, we show that this structural perturbation exists outside the first hydration shell of the ions.

Graphical abstract: Perturbation of water structure due to monovalent ions in solution

Article information

Article type
Paper
Submitted
06 Feb 2007
Accepted
12 Apr 2007
First published
04 May 2007

Phys. Chem. Chem. Phys., 2007,9, 2959-2967

Perturbation of water structure due to monovalent ions in solution

R. Mancinelli, A. Botti, F. Bruni, M. A. Ricci and A. K. Soper, Phys. Chem. Chem. Phys., 2007, 9, 2959 DOI: 10.1039/B701855J

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