The role of attraction in the phase diagrams and melting scenarios of generalized 2D Lennard-Jones systemsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 11 мая 2022 г.
Аннотация:Monolayer and two-dimensional (2D) systems exhibit rich phase behavior, compared with 3D systems, in particular, due to the hexatic phaseplaying a central role in melting scenarios. The attraction range is known to affect critical gas–liquid behavior (liquid–liquid in protein andcolloidal systems), but the effect of attraction on melting in 2D systems remains unstudied systematically. Here, we have revealed how theattraction range affects the phase diagrams and melting scenarios in a 2D system. Using molecular dynamics simulations, we have consideredthe generalized Lennard-Jones system with a fixed repulsion branch and different power indices of attraction from long-range dipolarto short-range sticky-sphere-like. A drop in the attraction range has been found to reduce the temperature of the gas–liquid critical point,bringing it closer to the gas–liquid–solid triple point. At high temperatures, attraction does not affect the melting scenario that proceedsthrough the cascade of solid–hexatic (Berezinskii–Kosterlitz–Thouless) and hexatic–liquid (first-order) phase transitions. In the case of dipolarattraction, we have observed two triple points inherent in a 2D system: hexatic–liquid–gas and crystal–hexatic–gas, the temperature of thecrystal–hexatic–gas triple point is below the hexatic–liquid–gas triple point. This observation may have far-reaching consequences for futurestudies, since phase diagrams determine possible routes of self-assembly in molecular, protein, and colloidal systems, whereas the attractionrange can be adjusted with complex solvents and external electric or magnetic fields. The results obtained may be widely used in condensedmatter, chemical physics, materials science, and soft matter.