Effect of size, shape and dimension on glass transition and Kauzmann temperature of Ag and Ta nanoparticles

A simple model is developed to calculate size, shape and dimension dependent glass transition (T_g) and kauzmann temperature (T_K) of nanoparticles (NPs). In this study, Silver (Ag) and Tantalum (Ta) NPs with spherical, tetrahedral, octahedral and icosahedral shapes accompanied with zero, one and two dimension, have been selected. The glass transition temperature and Kauzmann temperature decreases with the decrease in size of the nanoparticles irrespective of their shape and dimension. However in terms of shape; it is observed that the both temperatures of the nanoparticles follows the trend as (icosahedral, D) > (spherical, D) > (octahedral, D) > (tetrahedral, D) for selected nanoparticle. In terms of dimension, they are just reversed i.e. d=0 < d=1 < d=2 for a nanoparticle of selected size. The calculated values of glass transition and Kauzmann temperatures for Ag and Ta nanoparticles are compared with available MD simulation data and found consistent. (author)