Chromatic patchy particles: Effects of specific interactions on liquidă structure
Résumé
We study the structural and thermodynamic properties of patchy particleă liquids, with a special focus on the role of ``color,'' i.e., specifică interactions between individual patches. A possible experimentală realization of such ``chromatic'' interactions is by decorating theă particle patches with single-stranded DNA linkers. The complementarityă of the linkers can promote selective bond formation betweenă predetermined pairs of patches. By using MD simulations, we compare theă local connectivity, the bond orientation order, and other structurală properties of the aggregates formed by the ``colored'' andă ``colorless'' systems. The analysis is done for spherical particlesă with two different patch arrangements (tetrahedral and cubic). It isă found that the aggregated (liquid) phase of the ``colorless'' patchyă particles is better connected, denser and typically has stronger locală order than the corresponding ``colored'' one. This, in turn, makes theă colored liquid less stable thermodynamically. Specifically, we predictă that in a typical case the chromatic interactions should increase theă relative stability of the crystalline phase with respect to theă disordered liquid, thus expanding its region in the phase diagram.