Molecular Dynamic Simulation of Eu3+ ‐Doped Sodium Borate Glasses and Their Fluorescence Spectra

Abstract

A molecular dynamic simulation was performed for sodium borate glasses containing a small amount of Eu2O3 to investigate the local structures of cations in glass. A new potential VB‐B in the form ‐A exp[‐C(r ‐ 0.239)2] was added to the regular modified Born‐Mayer‐Huggins‐type potentials, ΦB‐B, ΦB‐O, and ΦO‐O, to account for the directional tendency of the borate network structure. With this potential added, both the radial distribution of sodium borate glasses observed by small‐angle X‐ray diffraction and the change in coordination number of boron with sodium content obtained by NMR agreed well with the simulation. The average coordination number of Ed3+ ions in the simulated glasses varied from 7.5 to 8.6, depending on the composition of the host sodium borate glasses. The inhomogeneous line width of the 5D0‐7Fz emission peak also changed, depending on the sodium content, with a maximum at 18 mol% NazO content; this result agrees well with experimental data obtained from laser‐induced fluorescence spectra.