Table 3. Calculated Adsorption Energies and O–Al Bond Distances for Acetate, Formate, and Methoxy on the (100)-γ-Al2O3 Surfacea without Dispersion Correction.
|
rO–Al [Å] |
Eads[eV] |
||||
|---|---|---|---|---|---|
| entry | oxy-carbon | PBEsol | DFTB3b | PBEsol | DFTB3b |
| #1 | methoxy | 1.84 | 1.79 (−0.05) | –1.36 | –1.40 (−0.04) |
| #2 | methoxy | 1.89 | 1.81 (−0.08) | –0.96 | –0.94 (+0.02) |
| #3 | ethoxy | 1.84 | 1.77 (−0.07) | –1.22 | –1.38 (−0.16) |
| #4 | ethoxy | 1.90 | 1.82 (−0.08) | –0.94 | –0.91 (+0.04) |
| #5 | ethoxy | 1.90 | 1.82 (−0.08) | –1.09 | –1.17 (−0.08) |
| #6 | formate | 1.91 | 1.81 (−0.10) | –0.98 | –0.90 (+0.09) |
| #7 | formate | 1.89 | 1.86 (−0.04) | –1.23 | –1.07 (+0.16) |
| #8 | formate | 1.90 | 1.86 (−0.04) | –0.98 | –0.79 (+0.19) |
| #9 | formate | 1.93 | 1.85 (−0.08) | –0.84 | –0.74 (+0.10) |
| #10 | acetate | 1.90 | 1.81 (−0.09) | –0.96 | –0.98 (−0.02) |
| #11 | acetate | 1.88 | 1.86 (−0.02) | –1.21 | –1.15 (+0.07) |
| #12 | acetate | 1.88 | 1.86 (−0.02) | –0.95 | –0.87 (+0.09) |
| #13 | acetate | 1.92 | 1.85 (−0.07) | –0.80 | –0.81 (−0.01) |
| #14 | propionate | 1.90 | 1.81 (−0.09) | –0.99 | –0.91 (+0.08) |
| #15 | propionate | 1.88 | 1.85 (−0.03) | –1.24 | –1.08 (+0.16) |
| #16 | propionate | 1.88 | 1.85 (−0.03) | –0.99 | –0.80 (+0.19) |
| #17 | propionate | 1.92 | 1.84 (−0.08) | –0.83 | –0.75 (+0.08) |
| #18 | bicarbonate | 1.90 | 1.81 (−0.09) | –1.01 | –1.18 (−0.17) |
| #19 | bicarbonate | 1.88 | 1.86 (−0.02) | –1.26 | –1.34 (−0.08) |
| #20 | bicarbonate | 1.89 | 1.86 (−0.03) | –1.01 | –1.07 (−0.06) |
| MAD | 0.06 | 0.09 | |||
a
Herein, the O atom refers to the one that belongs to the oxy-carbon species. The calculations were performed without dispersion correction.
b
Differences from the PBEsol method are shown in parentheses.