Solvent-mediated folding of a doubly charged anion.
The microsolvation of the suberate dianion, -O2C(CH2)6CO2-, with two separate charge centers was studied by photoelectron spectroscopy and molecular dynamics simulation one solvent molecule at a time for up to 20 waters. It is shown that the two negative charges are solvated in the linear suberate alternately. As the solvent number increases, the negative charges are screened and a conformation change occurs at 16 waters, where the cooperative hydrogen bonding of water is large enough to overcome the Coulomb repulsion and pull the two negative charges closer through a water bridge. This conformation change, revealed both from the experiment and from the simulation, is a manifestation of the hydrophilic and hydrophobic forces at the molecular level.
Yang
Xin
X
Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99352, USA.
Fu
You-Jun
YJ
Wang
Xue-Bin
XB
Slavícek
Petr
P
Mucha
Martin
M
Jungwirth
Pavel
P
Wang
Lai-Sheng
LS