MP2 Keywords
| Keyword | Effect |
|---|---|
| `Scaling none | scs |
OS f | Opposite-spin correlation scale factor |
SS f | Same-spin correlation scale factor |
DF | Density-fitting / RI-MP2 request |
Aux name | Auxiliary basis set for DF-MP2 |
KeepHalf | Keep half-transformed AO integrals |
DiscardVV | Discard virtual–virtual blocks (DF only) |
Skip tokens | Comma-separated skip tokens (e.g. Skip eri) |
Acc2E N | ERI threshold override for MP2 |
FreezeCore, FC | Use automatic chemically standard frozen core |
FreezeCore N, FC=N | Freeze exactly N lowest occupied orbitals |
Full, NoFC | Correlate all occupied orbitals |
Spin-Component Scaling
Scaling | Description |
|---|---|
none | Canonical MP2 |
scs | SCS-MP2 defaults: OS = 1.2, SS = 1/3 |
sos | SOS-MP2 defaults: OS = 1.3, SS = 0.0 |
Custom OS and SS values override the scaling defaults.
See MP2 Section for detailed descriptions and examples.