Structural and Elastic Behaviour of Sodalite Na8(Al6Si6O24)Cl2 at High-Pressure by First-Principle Simulations

Sodalite Na8(Al6Si6O24)Cl2 (space group P4¯3n) is an important mineral belonging to the zeolite group, with several and manyfold fundamental technological applications. Despite interest in this from different disciplines, very little known regarding its high-pressure elastic properties. The present study aims at filling knowledge gap, reporting equation of state moduli sodalite calculated a wide pressure range, −6 GPa 22 GPa. results were obtained Density Functional Theory simulations carried out Gaussian-type basis sets well-known hybrid functional B3LYP. DFT-D3 posteriori correction include van der Waals interactions physical treatment was also applied. parameters 0 absolute zero (0 K), i.e., K0 = 70.15(7) GPa, K’ 4.46(2) V0 676.85(3) Å3 are line properties derived stiffness tensor, agreement few experimental data reported literature. found mechanically unstable when compressed above 15.6