Abstract
The surface layer of coals and layered minerals: graphite, disulfides graphite, molybdenum disulfides, and molybdenum diselenides, is an ultrathin film with dimensions ranging from ~2 nm in the plane of the layers to ~6 nm perpendicular to these layers. This film contains three monolayers for graphite, four monolayers for MoS2, and five monolayers for MoSe2. The surface layer of minerals of these dimensions represents a 2D structure, distinct from a bulk crystal. All nanolayers within this layer also differ from one another due to size effects. Based on the concept of mineral nanolayers, as well as the results of the authors' research and data presented in the scientific literature, appropriate analytical calculations were performed, which made it possible to determine the thickness of the surface layer of coals and their relationship with gas content. It has been established that the deformation energy associated with mineral surface reconstruction determines the physical properties of nanolayers. This opens the way for analyzing such physical properties as surface tension and related effects (Seebeck, Peltier, and Thomson), specific heat capacity, and others. The conversion of deformation energy in layered minerals and coals into various forms of energy is examined. For coals, it has been shown that the primary crack length is determined by the thickness of the surface layer. It has been established that the layer thickness decreases with increasing metamorphism grade, surface energy increases, and specific heat capacity decreases. Surface nanoscale layers R (I) Layered minerals and coals represent an open quantum system in which quantum-size effects manifest themselves, leading to anomalous physical phenomena. The deformation energy generated in minerals during surface reconstruction reflects all the fundamental properties of bulk minerals that are of practical importance, particularly the formation of gas-bearing properties. The results of these studies form a new direction for scientific research into the physics of the surface layer of layered minerals, including coals.