Figure 1: Formation energy of Si NCs doped with B in a variety of configurations. Among B configurations at the NC surface, only those with the formation energy of Si NCs smaller than that of a Si NC doped with B2′ are presented. They are , , , , , , BH(α), H, BH(β), , , , , , , , , , , and BH2(α). Internal substitutional B atoms from subsurface to the NC center (2 (2′) → 3 (3′) → 4 (4′) → 5 → 6) are all shown. (Reprinted from [37] copyright 2011 American Chemical Society.)