Indicated by \(G_{\text{r}}\) or \(G_{\text{el}}\) if the repulsion is due to electric effects (\(g_{\text{r}}\) or \(g_{\text{el}}\) is taken for unit area of each of two flat and parallel surfaces). \(G_{\text{r}}\) (or \(G_{\text{el}}\)) is defined as \[G_{\text{r}}\,\text{(}\text{or}\,G_{\text{el}}\text{)} = \left[\int _{\text{final distance}}^{\infty }\text{Force} \;\text{d (distance)}\right]_{T,p}\]