Table 7.
Results of CASTEP calculations for Form I and Form IV at 3.10 GPa.
| Initial Structure | a [Å] | b [Å] | c [Å] | V [Å3] | Space Group | E [eV] | F [eV] | |
|---|---|---|---|---|---|---|---|---|
| Form I | Experimental (at 0 GPa) | 5.565 | 5.565 | 4.684 | 145.06 | P 4̅21m | ||
| GGA PBESOL | 5.237 | 5.237 | 4.574 | 125.47 | P 4̅21m | −2420.069 | −2416.303 | |
| GGA PBE TS | 5.282 | 5.282 | 4.649 | 129.68 | P 4̅21m | −2427.370 | −2423.576 | |
| GGA WC | 5.250 | 5.250 | 4.569 | 125.93 | P 4̅21m | −2424.673 | −2420.898 | |
| Form IV | Experimental (at 3.10 GPa) | 3.414 | 7.360 | 4.606 | 115.74 | P212121 | ||
| GGA PBESOL | 3.523 | 7.047 | 4.619 | 114.68 | P212121 | −2420.143 | −2416.369 | |
| GGA PBE TS | 3.474 | 7.166 | 4.683 | 116.56 | P212121 | −2427.574 | −2423.764 | |
| GGA WC | 3.545 | 7.028 | 4.617 | 115.03 | P212121 | −2424.731 | −2420.948 |