skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Molecular Mechanism of Specific Ion Interactions Between Alkali Cations and Acetate Anion in Aqueous Solution: A Molecular Dynamics Study

Journal Article · · Journal of Physical Chemistry B
DOI:https://doi.org/10.1021/jp301859z· OSTI ID:1047353

Specific ion interactions between the alkali cations (i.e., Li+, Na+ and K+) and an acetate anion in aqueous solution were studied using molecular dynamics simulation techniques and polarizable potential models. The ions-acetate systems were used as a model for understanding the interactions between ions and protein surfaces. We computed free energy profiles for different ion pairs using constrained mean force methods. Upon analyzing the computed free energy profiles for the Na+/K+-acetate ion-pairs, we observed a deeper contact ion minimum and also a larger association constant for the Na+-acetate pair compared to the corresponding K+-acetate pair. These observations help to demonstrate the preferential binding of Na+ over K+ to protein surfaces.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
1047353
Report Number(s):
PNNL-SA-85963; KC0301020; TRN: US201216%%212
Journal Information:
Journal of Physical Chemistry B, Vol. 116, Issue 25; ISSN 1520-6106
Country of Publication:
United States
Language:
English