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Y.-W. Huang et al.
B97D can predict smaller redistributed σ -electron population. Most hybrid functionals predicted redistributed σ -electron population within the range of 0.24–0.28.
However, it can be found that BMK and M052X functionals predict higher redistributed σ -electron population (∼0.31) and BHandH, M062X and BHandHLYP
predict lower one (∼0.22). The wavefunction methods HF and MP2 all predict quite
low redistributed σ -electron population of 0.20 and 0.23, respectively. No observable relation between the redistributed σ -electron population and CO S-T excitation
energy can be found for CO fcc-Pt 7–3 .
As can be seen in Fig. 11.4(d) for CO adsorption at fcc-Pt 9–9–9 , the redistributed σ -electron population only slightly decreases with the CO S-T excitation
energy increasing except in the case for BMK, BHandHLYP and BHnadH functionals. The BMK functional gives higher redistributed σ -electron population and
the BHandHLYP and BHnadH functionals gives lower one. Comparing with CO
adsorption at top-Pt 9–9–9 , it can be found that as the computed CO S-T excitation
energy increasing, the reduction of σ -repulsion for top site is more observable than
that for fcc site, and thus CO favors to adsorb at top site in those functionals which
can give better CO S-T excitation energy.
Figure 11.5 shows the redistributed π -electron population as respect to the CO ST excitation energy. As can be seen in Fig. 11.5(a) for CO adsorption at top-Pt 7–3 ,
the LDA(SVWN) predict quite high redistributed π -electron population of 0.76.
However, for most other GGA and hybrid functionals, the redistributed π -electron
populations are within the range of 0.4–0.5. The PW91 and BP86 functionals predict higher redistributed π -electron population (∼0.58) and BHandHLYP predicts
lower one (0.34). For CO adsorption at top-Pt 9–9–9 , as can be seen in Fig. 11.5(b),
it can be found that the BHandHLYP predicts quite low redistributed π -electron
population (0.38), but redistributed π -electron populations for most hybrid functionals are within 0.45–0.55. As can be seen in Fig. 11.5(c) that for CO adsorption
at fcc-Pt 7–3 , LDA and GGA functionals predict higher redistributed π -electron population comparing with hybrid functionals and WFT. For most hybrid functionals,
the predicted redistributed π -electron population are within the range of 1.0–1.2 except for the case of BHandHLYP and M05-2X (∼0.9). The predicted redistributed
π -electron population for HF and MP2 are 0.70 and 0.99, respectively. As can be
seen in Fig. 11.5(d) that for CO adsorption at fcc-Pt 9–9–9 , it can be found that the
B3PW91, PBE0, HSE03/06 and BMK functionals predict higher redistributed π -
electron population, and BHandHLYP predicts lower one (1.05) comparing with
other functionals. The predicted redistributed π -electron populations for most functionals are within the range of 1.15–1.28. No observable dependence between the
redistributed π -electron population and CO S-T excitation energy can be found for
CO adsorption at fcc-Pt 9–9–9 .
Figure 11.6 shows the π -electron population transferred from metal with respect
to the CO singlet-triplet excitation energy for CO adsorption at top site and fcc
site on Pt 7–3 and Pt 9–9–9 . As can be seen in Fig. 11.6(a) that for CO adsorption
at top-Pt 7–3 , the transferred π -electron population is decreased with the CO S-T
excitation energy increasing. Similar trends can also be seen in Fig. 11.6(b) that for
CO adsorption at top-Pt 9–9–9 . It implies that the effect of π -attraction through π -
back bonding is reduced with the CO S-T excitation energy increasing. In contrast,
Y.-W. Huang et al.
B97D can predict smaller redistributed σ -electron population. Most hybrid functionals predicted redistributed σ -electron population within the range of 0.24–0.28.
However, it can be found that BMK and M052X functionals predict higher redistributed σ -electron population (∼0.31) and BHandH, M062X and BHandHLYP
predict lower one (∼0.22). The wavefunction methods HF and MP2 all predict quite
low redistributed σ -electron population of 0.20 and 0.23, respectively. No observable relation between the redistributed σ -electron population and CO S-T excitation
energy can be found for CO fcc-Pt 7–3 .
As can be seen in Fig. 11.4(d) for CO adsorption at fcc-Pt 9–9–9 , the redistributed σ -electron population only slightly decreases with the CO S-T excitation
energy increasing except in the case for BMK, BHandHLYP and BHnadH functionals. The BMK functional gives higher redistributed σ -electron population and
the BHandHLYP and BHnadH functionals gives lower one. Comparing with CO
adsorption at top-Pt 9–9–9 , it can be found that as the computed CO S-T excitation
energy increasing, the reduction of σ -repulsion for top site is more observable than
that for fcc site, and thus CO favors to adsorb at top site in those functionals which
can give better CO S-T excitation energy.
Figure 11.5 shows the redistributed π -electron population as respect to the CO ST excitation energy. As can be seen in Fig. 11.5(a) for CO adsorption at top-Pt 7–3 ,
the LDA(SVWN) predict quite high redistributed π -electron population of 0.76.
However, for most other GGA and hybrid functionals, the redistributed π -electron
populations are within the range of 0.4–0.5. The PW91 and BP86 functionals predict higher redistributed π -electron population (∼0.58) and BHandHLYP predicts
lower one (0.34). For CO adsorption at top-Pt 9–9–9 , as can be seen in Fig. 11.5(b),
it can be found that the BHandHLYP predicts quite low redistributed π -electron
population (0.38), but redistributed π -electron populations for most hybrid functionals are within 0.45–0.55. As can be seen in Fig. 11.5(c) that for CO adsorption
at fcc-Pt 7–3 , LDA and GGA functionals predict higher redistributed π -electron population comparing with hybrid functionals and WFT. For most hybrid functionals,
the predicted redistributed π -electron population are within the range of 1.0–1.2 except for the case of BHandHLYP and M05-2X (∼0.9). The predicted redistributed
π -electron population for HF and MP2 are 0.70 and 0.99, respectively. As can be
seen in Fig. 11.5(d) that for CO adsorption at fcc-Pt 9–9–9 , it can be found that the
B3PW91, PBE0, HSE03/06 and BMK functionals predict higher redistributed π -
electron population, and BHandHLYP predicts lower one (1.05) comparing with
other functionals. The predicted redistributed π -electron populations for most functionals are within the range of 1.15–1.28. No observable dependence between the
redistributed π -electron population and CO S-T excitation energy can be found for
CO adsorption at fcc-Pt 9–9–9 .
Figure 11.6 shows the π -electron population transferred from metal with respect
to the CO singlet-triplet excitation energy for CO adsorption at top site and fcc
site on Pt 7–3 and Pt 9–9–9 . As can be seen in Fig. 11.6(a) that for CO adsorption
at top-Pt 7–3 , the transferred π -electron population is decreased with the CO S-T
excitation energy increasing. Similar trends can also be seen in Fig. 11.6(b) that for
CO adsorption at top-Pt 9–9–9 . It implies that the effect of π -attraction through π -
back bonding is reduced with the CO S-T excitation energy increasing. In contrast,