Structure and thermodynamic stability of carbon clathrates: A Monte Carlo study

• Published in: Solid state communications Vol. 152; no. 3; pp. 180 - 184
• Main Authors: Colonna, F., Fasolino, A., Meijer, E.J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2012; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; D. Crystal binding and equation of state; D. Phase transition; D. Thermodynamic properties; Elemental solids; Exact sciences and technology; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; D. Crystal binding and equation of state; D. Phase transition; D. Thermodynamic properties; Structure stability; Interatomic interaction; Thermodynamic stability; High temperature; Lattice parameters; Carbon; Bond lengths; Clathrates; High pressure; Monte Carlo methods; Equations of state; Radial distribution function; Simulated annealing; Ab initio calculations
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2011.11.011

Clathrates are strong, low density, fully sp 3 structures that have been found for several elements of the IV group. Carbon clathrates however are, as of now, hypothetical materials. Ab initio calculations at T = 0 K predict carbon clathrates to be metastable with remarkable mechanical and electronic properties. Here we study the behavior and structural stability of the type I C 46 carbon clathrates up to high temperature and pressure by means of Monte Carlo simulations based on an accurate model for the interatomic interactions. We find that the clathrate structure remains mechanically stable up to melting and we report the equilibrium structural parameters, thermal expansion, and equation of state. ► The first (simulation) study of carbon clathrate at finite temperature. ► Mechanical stability at high temperature. ► The high temperature, high pressure equation of state/structure.