  It has been hypothesized that liquid polyamorphism, the existence of multiple
amorphous states in a single component substance, may be caused by molecular or
supramolecular interconversion. A simple microscopic model [Caupin and
Anisimov, Phys. Rev. Lett., 127, 185701, (2021)] introduces interconversion in
a compressible binary lattice to generate various thermodynamic scenarios for
fluids that exhibit liquid polyamorphism and/or water-like anomalies. Using
this model, we demonstrate the dramatic effects of interconversion on the
interfacial properties. In particular, we find that the liquid-vapor surface
tension exhibits either an inflection point or two extrema in its temperature
dependence. Correspondingly, we observe anomalous behavior of the interfacial
thickness and a significant shift in the location of the concentration profile
with respect to the location of the density profile.
