Influence of size, shape and dimension on glass transition and Kauzmann temperature of silver (Ag) and tantalum (Ta) nanoparticles

Abstract

A simple model is developed for the investigation of size, shape and dimension dependent glass transition temperature (Tg) and Kauzmann temperature (TK) of nanoparticles. The model is based on thermodynamical quantity cohesive energy and is free from fitting parameters and approximations. To check the validity of the model, calculations on the size, shape and dimension dependent glass transition (Tg) and Kauzmann temperature (TK) are performed for silver (Ag) and tantalum (Ta) nanoparticles (NPs) of different shapes. The considered shapes are spherical, tetrahedral, octahedral and icosahedral accompanied with zero-, one- and two-dimensional geometries. Our results reveal that the Tg and TK strongly depend on the size of the nanoparticles. As the size of the NPs decreases, Tg and TK decrease. It is observed that both temperatures follow the trend as (icosahedral, D) > (spherical, D) > (octahedral, D) > (tetrahedral, D) for selected Ag and Ta nanoparticles. However, in terms of dimension, they show the d = 0 < d = 1 < d = 2 trend. The calculated values of glass transition and Kauzmann temperatures for both considered nanoparticles have good agreement with available molecular dynamics (MD) simulation and experimental data.