The Metal Geometry tool facilitates analysis of metal-binding sites. It lists potential metal-coordinating atoms (nearby nucleophilic heteroatoms) and suggests likely coordination geometries. An idealized geometry can be depicted with solid arrows, as shown in the figure for the octahedral coordination of Mn⁺⁺ by six atoms, and the coordination pseudobonds in the structure can be updated to match the chosen geometry.

BILD format was used in Chimera to annotate the barrel structure of green fluorescent protein with its centroid, major axis (red arrow), and an enclosing cylinder (shown with green hoops). The BILD file green.bild was generated with the python program green.py using the coordinates in green.pdb. Gallery entry courtesy of Mike Ess, Yeast Resource Center, University of Washington. (More samples...)