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Achieving the formation of target open crystalline lattices from colloidal particles is of paramount importance for their potential application in photonics. Examples of such desired structures are the diamond, tetrastack, and pyrochlore lattices. Here, we demonstrate that the self-assembly of tetravalent patchy particles results in the selective formation of cubic tetrastack crystals, both in the bulk and in the systems subjected to external fields exerted by the solid substrate. It is demonstrated that the presence of an external field allows for the formation of well-defined single crystals with a low density of defects. Moreover, depending on the strength of the applied external field, the mechanism of epitaxial growth changes. For weakly attractive external fields, the crystallization occurs in a similar manner as in the bulk, since the fluid does not wet the substrate. Nonetheless, the formed crystal is considerably better ordered than the crystals formed in bulk, since the surface induces the ordering in the first layer. On the other hand, it is demonstrated that the formation of well-ordered cubic tetrastack crystals is considerably enhanced by the increase in external field strength, and the formation of the thick crystalline film occurs via a series of layering transitions. [ABSTRACT FROM AUTHOR]

The ice surface is known for presenting a very small kinetic friction coefficient, but the origin of this property remains highly controversial to date. In this work, we revisit recent computer simulations of ice sliding on atomically smooth substrates, using newly calculated bulk viscosities for the TIP4P/ice water model. The results show that spontaneously formed premelting films in static conditions exhibit an effective viscosity that is about twice the bulk viscosity. However, upon approaching sliding speeds in the order of m/s, the shear rate becomes very large, and the viscosities decrease by several orders of magnitude. This shows that premelting films can act as an efficient lubrication layer despite their small thickness and illustrates an interesting interplay between confinement enhanced viscosities and shear thinning. Our results suggest that the strongly thinned viscosities that operate under the high speed skating regime could largely reduce the amount of frictional heating. [ABSTRACT FROM AUTHOR]

With an ever-increasing interest in water properties, many intermolecular force fields have been proposed to describe the behavior of water. Unfortunately, good models for liquid water usually cannot provide simultaneously an accurate melting point for ice. For this reason, the TIP4P/Ice model was developed for targeting the melting point and has become the preferred choice for simulating ice at coexistence. Unfortunately, available data for its dynamic properties in the liquid state are scarce. Therefore, we demonstrate a series of simulations aimed at the calculation of transport coefficients for the TIP4P/Ice model over a large range of thermodynamic conditions, ranging from T = 245 K to T = 350 K, for the temperature, and from p = 0 to p = 500 MPa, for the pressure. We have found that the self-diffusion (shear viscosity) exhibits smaller (increased) values than TIP4P/2005 and experiments. However, rescaling the temperature with respect to the triple point temperature, as in a corresponding states plot, we find that TIP4P/Ice compares very well with TIP4P/2005 and experiment. Such observations allow us to infer that despite the different original purposes of these two models examined here, one can benefit from a vast number of reports regarding the behavior of transport coefficients for the TIP4P/2005 model and utilize them following the routine described in this paper. [ABSTRACT FROM AUTHOR]