Densest versus Jammed Packings of Two-Dimensional Bent-Core Trimers

We identify the maximally dense lattice packings of tangent-disk trimers with fixed bond angles (θ = θ0) and contrast them to both their nonmaximally-dense-but-strictly-jammed lattice packings as well as the disordered jammed states they form for a range of compression protocols. While only θ0 = 0, 60◦, and 120◦ trimers can form the triangular lattice, maximally-dense maximally-symmetric packings for all θ0 fall into just two categories distinguished by their bond topologies: half-elongated-triangular for 0 \u3c θ0 \u3c 60◦ and elongated-snub-square for 60◦ \u3c θ0 \u3c 120◦. The presence of degenerate, lower-symmetry versions of these densest packings combined with several families of less-dense-but-strictly jammed lattice packings act in concert to promote jamming