heptagon

n.

七角形，七边形；

Pentagons and heptagons in the first water layer on Pt(111).
Carbon arc production of heptagon-containing fullerene[68].
Pentagons, heptagons and negative curvature in graphite microtubule growth
Stability of dislocation defect with two pentagon-heptagon pairs in graphene
A Symbol of Uniqueness: The Cluster Bootstrap for the 3-Loop MHV Heptagon
Structural and electronic properties of pentagon-heptagon pair defects in carbon nanotubes.
The nature of strength enhancement and weakening by pentagon-heptagon defects in graphene
The nature of strength enhancement and weakening by pentagon-heptagon defects in graphene.
Chlorination of C86 to C84Cl32 with Nonclassical Heptagon‐Containing Fullerene Cage Formed by Cage Shrinkage
Two-dimensional tiling by rubrene molecules self-assembled in supramolecular pentagons, hexagons, and heptagons on a Au111 surface.