Figure A2.

Step-by-step growth of the nanoshell shown by a series of snapshots. In steps 1, 2, and 4, a single new subunit is added at the location with the smallest opening angle. In step 3, the small opening wedge is closed without inserting another subunit, forming a pentamer. In step 5, a new subunit is inserted and bound along both edges, forming a hexamer. To see this figure in color, go online.