Table 3. Adsorption Sites and Adsorption Energies (E_ad) (in kcal mol^–1) for NH_x (x = 0–3) Species and H Adsorbed on a Ni(111) Surface.

		Eada
adsorbate	adsorption sites	PBE	PBEb	PBEc	PBE-D3	expt
NH3	atop	–17.0	–17.3	–15.0	–26.0	–17.0d
NH2	bridge	–61.9	–63.0	–60.0	–69.7
NH	fcc	–103.8	–105.4	–101.0	–111.0
N	fcc	–121.0	–122.2	–119.7	–125.7
H	fcc	–64.5	–64.8	–64.6	–68.3

^aZPE correction is included within the computed adsorption energy.

^bReference (33).

^cReference (47).

^dReference (46).