In a search for a shape maximizing packing fraction for two-dimensional   random sequential adsorption
  Random sequential adsorption (RSA) of various two dimensional objects is studied in order to find a shape which maximizes the saturated packing fraction. This investigation was begun in our previous paper [Cie\'sla et al., Phys. Chem. Chem. Phys. 17, 24376 (2015)], where the densest packing was studied for smoothed dimers. Here this shape is compared with a smoothed $n$-mers, spherocylinders and ellipses. It is found that the highest packing fraction out of the studied shapes is $0.58405 \pm 0.0001$ and is obtained for ellipses having long-to-short axis ratio of $1.85$, which is also the largest anisotropy among the investigated shapes. 
Micha{\l} Cie\'sla, Grzegorz Paj\k{a}k and Robert M. Ziff
cond-mat.mtrl-sci cond-mat.stat-mech