# Range and mechanical properties in colloidal gels ###### tags: `gels` `glasses` --- --- ### Owners (the only one with the permission to edit the main test) Giuseppe, Mehdi --- --- ## Background The goal of this project is to investigate the properties of colloidal gels, as obtained by arrested phase separation, as function of the interaction range. ### The Model We will use the new Frenkel model that can be found here: [Wang et al. The Lennard-Jones potential: when (not) to use it](https://sci-hub.se/10.1039/C9CP05445F). It is basically a potential of variable range with smooth force and potential cut-off. ## Plans ### The model We will use, details in the papers, $\mu =1$ and $\nu =1$. As a cut-off, we will use two values: $r_c =1.2$ and $r_c = 2.0$ that are used in the paper to generate two phase diagram in the VDW (the fomer) and colloidal (limit): | $r_c =2.0$ | $r_c =1.2$ | | -------- | -------- | | ![](https://i.imgur.com/nQDXHqZ.png) | ![](https://i.imgur.com/LySJcJR.png) We will use a 50/50 binary mixture with diameters $\sigma_s 1.0$ and $\sigma_L =1.2$. This should avoid any crystallization. I suggest that we will use a total number density $\rho = 0.17502376$, equivalent to $\phi =0.25$. For the monodisperse case, $\rho=0.5$ is equivalent to $\phi=0.2618$. ### Quenching protocol TBD (see below) ## To Do :::success green is for finished tasks ::: ### Gel assembly and structure We will quench from high temperature the two mixtures * Choose carefully a target temperature $T_f$, (perhaps is worth) * Explore different quenching rates * NVT dynamics * Structure Factors, $U(t)$, $P(t)$ ##### OPEN QUESTIONS * Role of the range on the finale structure??? * Role of the quench rate?? ### Mechanical properties This will come after we pinned down the statics. :::success * step finished ::: * TBD ##### OPEN QUESTIONS * ? ## OPEN BIG QUESTIONS * What is the role of range in the mechanical properties of gels? * Brittle? Ductile?