Structural properties of amorphous Al2O3·2SiO2 nanoparticles

• Published in: Molecular simulation Vol. 34; no. 1; pp. 29 - 34
• Main Authors: Linh, N.N., Hoang, V.V.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01.01.2008
• Subjects: 61.43.Bn; 61.46-w; 78.55.Qr; amorphous aluminosilicate; nanoparticles; nanoscale materials
• ISSN: 0892-7022; 1029-0435
• DOI: 10.1080/08927020801930521

Structural properties of amorphous Al 2 O 3 ·2SiO 2 (denoted as AS 2 ) spherical nanoparticles have been studied in a model with different sizes of 2, 3 and 4 nm under non-periodic boundary conditions with the Born-Mayer type pair potentials via molecular dynamics (MD) simulation. We studied structural properties via the partial radial distribution functions (PRDFs), coordination number distributions, bond-angle distributions and interatomic distances. Moreover, the radial density profile in nanoparticles was found. Calculations show that size effects on structure of a model are significant and calculated data differ from those obtained previously in the bulk counterpart. We found that if the size is larger than 3 nm, amorphous AS 2 nanoparticle has a distorted tetrahedral network structure with the mean coordination number Z Al-O  ≈ 4 and Z Si − O  ≈ 4. The existence of triclusters in nanoparticles and size dependence of tricluster composition have been found and discussed. Furthermore, we also showed surface structure and surface energy of nanoparticles.