The effect of temperature on the patterning of water molecules located remotely from a single SO42− ion in aqueous nanodrops was investigated for nanodrops containing between 30 and 55 water molecules using instrument temperatures between 135 and 360 K. An SO42− dianion clearly affects the hydrogen bonding network of water to at least ∼0.71 nm at 135 K and ∼0.60 nm at 340 K, consistent with an entropic drive for reorientation of water molecules at the surface of warmer nanodrops. These distances represent remote interactions into at least a second solvation shell even with elevated instrumental temperatures. The results herein provide new insight into the extent to which ions can structurally perturb water molecules even at temperatures relevant to Earth’s atmosphere, where remote interactions may assist in nucleation and propagation of nascent aerosols.
Matthew J DiTucci, Christiane N Stachl, Evan R Williams
Chemical science 9 (16), 3970-3977 (2018)
