Herein we correlate secondary structure perturbation with changes in the solid-state molecular architectures of an elongated hexagonal plate-shaped foldecture derived from the self-assembly of rigid 12-helical beta-peptide foldamers to which a flexible C-terminus alpha-leucine moiety has been appended. This study provides the first complete characterization of the directional molecular packing patterns of individual foldamer components within a foldecture, from which a 3D molecular-level picture of the entire foldecture was unambiguously constructed.