The purpose of this paper was to approach the structure of gadolinium-lead-tellurate glasses with compositions xGd(2)O(3) (100-x)[7TeO(2)center dot 3PbO], x = 0-90 mol% using the X-ray diffraction, DFT calculations, FTIR, EPR and UV-VIS spectroscopy. Our results show that the doping with gadolinium ions will deform the Te-O-Te linkages, will affect the length of Te=O bonds and the accommodation of the network with excess of oxygen will be realized by the reorganization of the tellurate structural units. These affinities pronounced of the lead and gadolinium cations towards tellurium atoms yield the formation of the Pb(2)Te(3)O(8) and Gd(2)Te(6)O(15) crystalline phases because tellurate structural units can adopt a variety of structures due to the presence of the lone-pair electrons. (C) 2011 Elsevier B.V. All rights reserved.