Structures of cationic and anionic polyelectrolytes in aqueous solutions: the sign effect

Abstract

In this study, we use molecular dynamics simulation to explore the structures of anionic and cationic polyelectrolytes in aqueous solutions. We first confirm the significantly stronger solvation effects of single...

Controllable Transition Metal-Directed Assembly of [Mo2O2S2]2+ Building Blocks into Smart Molecular Humidity-Responsive Actuators

“…To fundamentally comprehend the mechanism for humidity actuation process at the molecular level, we further employ MD simulation to study the adsorption of water molecules in and around a single { Bi 8 Mo 48 } cluster and in the Bi 8 Mo 48 -PDDA complex. Herein, the model is developed based on our previous simulations and other works, − and the simulations were performed using a large-scale atomic/molecular massively parallel simulator (LAMMPS); please see the details (Figure S22) in the Supporting Information. Figure a,b shows the top and side views of the simulation snapshots for water aggregation near a single { Bi 8 Mo 48 }, and Figure c,d displays the radial distribution functions of counterions [ g c/i ( r )] and water molecules [ g c/w ( r )] around { Bi 8 Mo 48 }.…”

“…With time evolution from t = 0.002 ns to t = 2 ns, almost all counterions adsorb near { Bi 8 Mo 48 }; meanwhile, the water molecules gradually accumulate inside and around the hollow { Bi 8 Mo 48 } cage through hydrogen-bonding and solvation interactions, as shown by the variations in peaks of g c/i ( r ), g c/w ( r ) and the Supporting Video SV4. Note that water molecules enriching inside the { Bi 8 Mo 48 } cage even cause some counterions to dissociate from the surface and remain at the { Bi 8 Mo 48 } center through the solvation effect. ,, …”

“…Note that water molecules enriching inside the {Bi 8 Mo 48 } cage even cause some counterions to dissociate from the surface and remain at the {Bi 8 Mo 48 } center through the solvation effect. 47,48,51 Furthermore, Figure 4e,f shows the typical simulation snapshots of water bead adsorption in the Bi 8 Mo 48 -PDDA complex, and Figure 4g−j shows the corresponding water [d w (r)] and Bi 8 Mo 48 -PDDA [d m (r)] distributions in the simulation box as well as the radial distribution functions of water [g c/w (r)] and PDDA monomers [g p/w (r)] around the {Bi 8 Mo 48 } centers. Our simulations demonstrated that the anionic {Bi 8 Mo 48 } cages and cationic PDDA polymers can form highly condensed complexed structures through strong electrostatic interactions.…”

Developing Dawson-Type Polyoxometalates Used as Highly Efficient Catalysts for Lignocellulose Transformation

“…Herein, the pp-ol and ionic species were coarse-grained as spherical beads and the simulations were performed in the canonical (NVT) ensemble through the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) . The model was constructed based on our previous simulations and other studies; − please refer to the Supporting Information for the efficacy of the model (Figure S15) and simulation details. In Figure a,b, the representative simulation snapshots of the pp-ol/Bet + /Cl – and pp-ol/Ch + /Cl – solutions at the temperature of T ≈ 140 °C are displayed.…”

Control of Diblock Copolyelectrolyte Morphology through Electric Field Application

“…In the current work, we only consider the intermediate immiscibility between the hydrophobic blocks and the polyelectrolytes through the settings of ϵ LJ and r c in eq . In addition, as demonstrated by our previous studies and other references, the effects of ion solvation and the response of charge-neutral dipolar components to the electric field also serve as important factors that can alter the thermodynamics of the ionic soft-condensed system; ,,− nevertheless, in the current study, we ignore these effects and consider the system as the dielectric continuum.…”