Numerical investigation of the influence of the history on the local structure of glasses

By means of molecular dynamics simulations and the Voronoi tessellation, we study the influence of the history on the low temperature characteristics of soft sphere and silica glasses. The quench from the liquid is interrupted at an intermediate temperature $T_i$ for a given relaxation time, and then the cooling process is continued down to 0K. The local structure at 0K depends on the temperature $T_i$ and the effect is larger for $T_i$ close to the glass transition temperature $T_g$. This dependence, coherent with recent results, is expected in the strong glass former where the characteristics of a particular state depend on its history. In the soft-sphere case, because of crystallization effects, the dependence of the local structure of the glassy samples on their history can only be detected in the supercooled liquid region.