The transparent glasses 55 P2O 5 - (45-x) Na2O - xLi2O where (x=0, 3, 10, 15, 30, 35) were prepared by conventional melt quenching technique. Structural and characterization have been investigated by using X-Ray diffraction (XRD) and the results show that all samples are amorphous structure. The glass transition (Tg) and crystallization temperature (Tc) are evaluated using the differential thermal...