Bond compression bulk modulus and Poisson's ratio of the polycomponent silicate glasses

The theoretical bulk modulus and Poisson's ratio of the 65SiO(2)-15PbO-5CaO-(15-X)K2O-XNa2O glass system (X = 0-15 mol%) have been calculated using the bond compression model. The atomic ring size of the network has been also obtained for each sample according to the ring deformation model. These parameters have been interpreted quantitatively in terms of the most important structure factors. The composition dependence of these parameters showed that the elasticity and hence the response of this glass system is influenced by the chemical nature of the modifying oxides. Moreover, variation of the estimated atomic ring size with the ratio of bond compression (K-bc) to experimental (K-e) bulk modulus was studied to obtain more information about the structure of these glasses. The results showed that the small values of K-bc/K-e are attributed to the very close (small-ringed) three-dimensional network of these glasses. (C) 2001 Elsevier Science B.V. All rights reserved.