Affordable Access

Publisher Website

He incorporation and diffusion pathways in pure and defective zircon ZrSiO4: A density functional theory study

Authors
Journal
Chemical Geology
0009-2541
Publisher
Elsevier
Publication Date
Volume
258
Identifiers
DOI: 10.1016/j.chemgeo.2008.10.015
Keywords
  • Zircon
  • Helium
  • Point Defect
  • Diffusion Pathways
  • Activation Energy
Disciplines
  • Mathematics

Abstract

Abstract In this paper, we report a detailed study of helium (He) incorporation and diffusion pathways in the perfect and defective zircon lattice. Ab initio methods based on Density Functional Theory (DFT) were used to calculate the structural features, the solution energies in interstitial sites in the perfect zircon and in vacancy sites of the defective lattice and He diffusion pathways in these systems. We show that the mode of He incorporation in the perfect zircon is influenced mainly by the topological features of the lattice, promoting site preference of He towards accommodation in the interstitial sites present in the middle of c cylinder channels. The presence of defect species in the form of lattice vacancies and interstitials has a significant effect on He solubility and diffusivity in the lattice, where the ability of lattice vacancies to act as physical traps or repulsive sites depends greatly on the electronic nature of the vacancy, which can enhance solubility of He in the lattice and affect the kinetics of He mobility in zircon mineral.

There are no comments yet on this publication. Be the first to share your thoughts.