Sleeve bearings have been designed and modeled in atomic detail
Sleeve bearings based on polycyclic covalent structures can readily be designed and modeled using industry-standard molecular mechanics software. The GIF animation to the left shows the motion of a typical small sleeve bearing in the absence of thermal vibration (approximately the same as the mean motion at nonzero temperatures). Note that atoms near the interface between shaft and sleeve undergo small, cyclic displacements. These motions are smooth, however, and symmetry properties of the structure ensure low barriers to rotation (< 0.002 zJ in an MM2 calculation the characteristic thermal vibrational energy at room temperature is about 4 zJ).
The second panel shows a bond-oriented representation of the same structure, with atomic positions and molecular bonds as described in this PDB file. In his paper describing bearing symmetry properties, Ralph Merkle illustrates some elegant designs, based on graphite and diamond lattices, containing only carbon and hydrogen.