Fig. 6: NBO analysis of antiparallel PPII helices, 2D model.
From: Orientation affects hydrogen bonding cooperativity in polyproline II helical bundles
A Mean occupancy (q) of the corresponding σ*(NH/CαHα) orbitals and B mean stabilization energy (E(2)) of the corresponding n(O)/σ(CO)/π(CO)→σ*(NH/CαHα) electron delocalization for each CO···HN (squares), CO···HαCα proximal (right triangles) and CO···HαCα distal (left triangles) H-bond between the antiparallel PPII helices of the 2D computational model. The ab interface for the different systems is indicated in blue; the bc interface, in red, and the cd interface, in green.
