Plastic deformation of orthoenstatite and the ortho- to high-pressure clinoenstatite transition: a metadynamics simulation study |
| |
Authors: | Sandro Jahn Roman Martoňák |
| |
Institution: | (1) Department 4, GeoForschungsZentrum Potsdam, Telegrafenberg, 14473 Potsdam, Germany;(2) Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F2, 84248 Bratislava, Slovakia |
| |
Abstract: | Atomic-scale mechanisms of plastic deformation in orthoenstatite, MgSiO3 are studied by computer simulation methods. The combined use of metadynamics and molecular dynamics allows a direct observation
of the structural changes during the creation of stacking faults in the (100) plane. A sequence of slip deformations in two
different (100) planes at P = 15 GPa and T = 1,000 K reveals a probable transformation mechanism for the ortho- to high-pressure clinopyroxene transition. Each of the
observed slips consists of at least four partial deformations crossing high-energy intermediate structures. In agreement with
experimental studies, both (100)010] and (100)001] slip systems are activated in the deformation process. The observation
of a dominant (100)001] single slip system in pyroxenes may be related to the fact that high-energy intermediate dislocations
with (100)010] component are not stable on geological or experimental timescales. |
| |
Keywords: | Molecular dynamics Metadynamics Phase transition Enstatite MgSiO3 Orthopyroxene Clinopyroxene |
本文献已被 SpringerLink 等数据库收录! |
|