Boron-hydrogen complexes in diamond

Boron in diamond traps hydrogen forming passive B_s–H pairs. Boron trapping two deuterium atoms has been speculated as forming a shallow donor (0.23–0.34 eV below the conduction band). We present the results of first-principles calculations of boron complexes with 2–4 hydrogen atoms. The binding energy of the second and subsequent H atoms is small and none of the structures found are shallow donors. We also present the structure of interstitial boron, the boron-vacancy complex, and their interaction with hydrogen.