Table 2. Calculated Bond Length of HF Molecule and Cohesion Energy (Ecoh) of Na Crystal Using Different Exchange–Correlation Functionals and Their Difference with the Experimental Valuea.
| XC | RH–F (Å) | ΔR (Å) | Ecoh (kJ mol–1) | ΔE (kJ mol–1) |
|---|---|---|---|---|
| Pade | 0.9367 | 0.0199 | –96.4 | 12.6 |
| PBE | 0.9273 | 0.0105 | –117.7 | –8.7 |
| BLYP | 0.9402 | 0.0234 | –91.8 | 17.2 |
| B3LYP | 0.9280 | 0.0112 | –120.5 | –11.5 |
| PBE0 | 0.9358 | 0.0190 | –121.2 | –12.2 |
| experimental value | 0.9168 | –109.0 |
a
RH–F represents the bond length of HF; ΔR represents the difference between the calculated value and the experimental value of HF bond length; Ecoh represents the cohesion energy of Na crystal; and ΔE represents the difference between the calculated value and the experimental value of the cohesion energy.