arXiv subjects

Jacobo Troncoso

Publications and source records attributed to Jacobo Troncoso.

3 recordsLinked to original sources

arXiv2026

Theory of supercooled water

We introduce a model of water contemplating true supercooled-liquid states that, as such, are metastable with respect to the crystalline-solid ones. Its numerical solutions reproduce from Speedy-Angell's stability-limit picture to Poole et al.'s metastable liquid--liquid criticality. The real existence of a liquid--liquid critical point is found to gain significant theoretical plausibility from a hitherto unnoticed analogy with the ``inversion thermodynamics'' of Joule-Thomson gas throttling process and, by extension, with the equivalent phenomenology exhibited by black holes.

cond-mat.stat-mech↗

arXiv2026

Viscosity as a Smoking Gun for Complex Formation in Solution: Fe$^{2+}$ and Mg$^{2+}$ Chlorides as Examples

Electrolyte solutions at high concentration are indispensable and yet poorly understood. In particular, the extent of speciation -- the formation of complexes composed of multiple species -- in concentrated ionic solutions is very challenging to obtain theoretically and experimentally, but can have a strong effect on solution properties. The literature is rife with contradictory estimates of speciation from experiments. We find that speciation affects transport properties, and is therefore, a prerequisite to accurately model concentrated solutions. We turn this to our advantage by showing that the viscosity can be used to determine the extent of complexation in concentrated aqueous solutions. Results of simulations as well as experimental measurements are presented. The atomistic Madrid-2019 force-field is extended to model FeCl$_2$. Solutions of FeCl$_2$ and MgCl$_2$ are compared and the observed difference in viscosity explained by more complexation in the former, a conclusion supported by recently reported X-ray absorption and neutron scattering experiments.

physics.chem-ph↗

arXiv2023

Ising Model for the Freezing Transition

A spin-1 Ising model incorporating positional order to a standard lattice gas with no attractive interactions is introduced and found to be consistent with all known attributes of the freezing transition of the hard-sphere system. Implementation of attractive interactions in a fairly natural way then allows every aspect of the phase diagram of a simple substance to be reproduced. The \emph{whole} phase behavior of such sort of substances is thus found to sharply manifest the van der Waals picture highlighting the relevance of harsh repulsive forces.

cond-mat.stat-mech↗