  Assembly of spherical colloidal particles into extended structures, including
linear strings, in the absence of directional interparticle bonding
interactions or external perturbation could facilitate the design of new
functional materials. Here, we use methods of inverse design to discover
isotropic pair potentials that promote the formation of single-stranded,
polydisperse strings of colloids "colloidomers" as well as size-specific,
compact colloidal clusters. Based on the designed potentials, a simple model
pair interaction with a short-range attraction and a longer-range repulsion is
proposed which stabilizes a variety of different particle morphologies
including (i) dispersed fluid of monomers, (ii) ergodic short particle chains
as well as porous networks of percolated strings, (iii) compact clusters, and
(iv) thick cylindrical structures including trihelical Bernal spirals.
