Correlation between acoustical and structural parameters in some oxide glasses Amin Abd El-Moneim Physics Department, Faculty of Science, Zagazig University, Zagazig, Egypt abstract article info Article history: Received 12 June 2014 Received in revised form 1 September 2014 Accepted 10 September 2014 Available online 19 September 2014 Keywords: Glass; Acoustical property; Elastic modulus; Attenuation coefficient; Microstructure Correlation between acoustical and structural parameters has been carried out in TiO 2 –Na 2 O–CaO–P 2 O 5 , ZnO– PbO–B 2 O 3 and BaO–TeO 2 glass systems. The correlation is based on the recently presented Abd El-Moneim semi-empirical formulas, which relate the room temperature ultrasonic attenuation coefficient with oxygen den- sity, average atomic ring size, first-order stretching force constant and experimental bulk modulus of the glass. Fractal bond connectivity and mean atomic volume have also been evaluated and interpreted in terms of compo- sition to deduce changes in the structure of the glass. Furthermore, values of the theoretical bulk modulus have been calculated on the basis of Rocherulle et al. model and compared with the corresponding observed values. It has been found that, majority of the studied glass samples have two-dimensional structure and the network strength changes in the order BaO–TeO 2 glasses ≺ TiO 2 –Na 2 O–CaO–P 2 O 5 glasses ≺ ZnO–PbO–B 2 O 3 glasses. Abd El-Moneim semi-empirical formulas can be applied successfully to predict changes of ultrasonic attenuation co- efficient in these glasses at room temperature. Also, Rocherulle et al. model is valid for majority of the investigat- ed glass samples. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Acoustical properties play a significant role in understanding the structural characteristics of glasses, since they are directly related to the microscopic structure through the behavior of the network formers and modifiers [1–13]. Recently, the non-destructive ultrasonic pulse- echo technique has been found to be one of the best tools used for evaluating the acoustical parameters of glasses, such as elastic moduli, micro-hardness, Poisson's ratio, ultrasonic attenuation coefficient and Debye temperature. Extensive studies on the acoustical and structural properties of borate, phosphate, silicate and tellurite glasses have been reported in the recent years in view of their technological applications [1–13]. In addition, attempts have been made to estimate elastic moduli and Poisson's ratio of glasses from packing density and dissociation energy per unit volume of chemical oxides that constituent the glass network [4,6,14–17]. The most widely used model is that proposed by Makishima and Mackenzie [14,15] and extended thereafter by Rocherulle et al. [17] to oxynitride glasses. Recently, Abd El-Moneim [18–22] presented number of studies on the correlation between ultrasonic attenuation coefficient and structur- al parameters of oxide glasses. A model of two semi-empirical formulas, which correlate the experimentally measured ultrasonic attenuation coefficient at room temperature with oxygen density, average atomic ring size, first-order stretching force constant and experimental bulk modulus, was reported [19]. These semi-empirical formulas have been verified for TiO 2 -doped CaO–Al 2 O 3 –B 2 O 3 , Ag 2 O–V 2 O 5 –TeO 2 and RO– Al 2 O 3 –B 2 O 3 (R = Mg, Ca or Sr) glass systems [20,21]. More recently, Abd El-Moneim [22] derived a new semi-empirical formula, which cor- relates the room temperature ultrasonic attenuation coefficient with packing density, dissociation energy per unit volume and first-order stretching force constant of the glass. The same author verified his semi-empirical formula for TiO 2 -doped CaO–Al 2 O 3 –B 2 O 3 and Ag 2 O– V 2 O 5 –TeO 2 glass systems [22]. The applicability of Abd El-Moneim model [19,22] for a wide variety of phosphate, borate, gemanate, tellurite and silicate glasses is worth demonstrating. Recently, the acoustical properties of TiO 2 –Na 2 O–CaO– P 2 O 5 , ZnO–PbO–B 2 O 3 and BaO–TeO 2 glass systems have been studied using ultrasonic pulse-echo technique [7,10,11]. In the present work, the validity of Abd El-Moneim semi-empirical formulas [19,22], which correlate the room temperature ultrasonic attenuation coefficient with oxygen density, average atomic ring size, first-order stretching force constant and experimental bulk modulus, has been demonstrated for these glass systems. Special attention is also given on the structure of the glass by evaluating and discussing the compositional dependence of fractal bond connectivity and mean atomic volume. Finally, the Journal of Non-Crystalline Solids 405 (2014) 141–147 E-mail address: aminabdelmoneim@hotmail.com. http://dx.doi.org/10.1016/j.jnoncrysol.2014.09.014 0022-3093/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of Non-Crystalline Solids journal homepage: www.elsevier.com/ locate/ jnoncrysol