Molecular dynamics simulations with an umbrella potential function in solution were carried out to obtain the potential of mean force for sodium-dimethyl phosphate (Na+-DMP-) and sodium-methyl phosphate (Na+-MP2-). The Na+-DMP- showed two minima in pmf profile, a less stable minimum of ca. 3.5 Å and a more stable minimum of ca. 5.0 Å, resulting in direct and indirect contact between two ions. On the other hand, the Na+-MP2- showed one prominent minimum in pmf profile, at approximately ca. 4.5 Å. Water molecules around Na+-DMP- better formed a hydrogen-bonded network than around Na+-MP2-, showing a stronger interaction between water and the Na+-MP2-.
Bibliographical noteFunding Information:
This work was supported in part by the Korea Research Center for Theoretical Physics and Chemistry. NS KANG would like to thank the Department of Chemistry of Soongsil University for the financial support of the BK program.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry