which fall off with distance as a power law and do not have a cutoff beyond which the interaction is zero. When cooling from the liquid phase, the glass transition is known to occur around $\Gamma=1.45$ [@Barrat90].

We have looked for phase separation of the two types of spheres by examining the distribution of large and small spheres in the neighborhood of large spheres and in the neighborhood of small spheres. We see no evidence for phase separation at either high ($T=1.5$) or low ($T=0.15$) temperatures at a density of $\rho=0.6$.

Relaxation Times and Mode Coupling $T_C$
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As points of reference for the time and temperature scales, it is useful to find the mode coupling $T_C$ and the $\alpha$ relaxation times. We can find the relaxation times using the intermediate scattering function $F(\vec{k},t)$ which is a useful probe of the structural relaxation. It is the spatial Fourier transform of the van Hove correlation function $G(\vec{r},t)$ and the inverse time transform of the dynamic structure factor $S(\vec{k},\omega)$. There are two different types of intermediate scattering function: the self (incoherent) intermediate scattering function $F_{s}(\vec{k},t)$ and the full (coherent) intermediate scattering function $F(\vec{k},t)$.

In a computer simulation, the self (incoherent) part of 