Fig. 7: Guided excitation of a boundary mode along the heavy-boundary.

a During molecular dynamics simulations at 1 K, all non-hydrogen atoms of the molecule circled and highlighted in red are excited by an oscillating force (with a period of 0.733 ps or 45.5 cm⁻¹ and a force constant of 123.4 pN). The excitation occurs in the direction corresponding to the eigenmode of the single-molecule element depicted in Fig. 6e. The zoomed-in area shows the eigenvector’s components of the excited molecule, whose angles with respect to the xy-plane are shown using the colormap. b The root mean square deviation (RMSD) from the initial minimised configuration for each molecule (with colours corresponding to those in panel a) shows fluctuations that propagate up to the 4th boundary neighbour. Each RMSD data set is offset by 0.25 Å relative to its (second) nearest neighbour along the (boundary) bulk for clarity. Same-seed trajectories without excitation are provided in the Supplementary Information Fig. 15. Arrows in panel a serve as a guide to the eye for the RMSD fluctuations in b. Source data are provided as a Source Data file.