[guess]¶
The [guess] section controls initial orbitals, JSON restart files, and manual
MO swaps. Most users can start with the default Huckel guess.
Minimal Example¶
[guess]
type=huckel
Keywords¶
type¶
| Field | Value |
|---|---|
| Type | string |
| Default | huckel |
| Values | huckel, modhuckel, hcore, json, auto, sap, minao |
| Used by | initial density/orbital construction |
Selects the initial guess mode.
| Value | Meaning |
|---|---|
huckel |
Native extended-Huckel style guess. |
modhuckel |
Modified Huckel guess. |
hcore |
Core-Hamiltonian guess. |
json |
Read orbitals and molecular data from a JSON restart file. |
auto |
Read file if it exists; otherwise fall back to Huckel. |
sap |
Superposition-of-atomic-potentials guess. |
minao |
Projected minimal-basis density guess. |
Use json for exact restarts and auto for workflows that may or may not have
a previous restart file.
file¶
| Field | Value |
|---|---|
| Type | string |
| Default | empty |
| Used by | type=json, type=auto |
Path to a JSON restart file. With type=json, the file must exist. With
type=auto, OpenQP uses it when present and otherwise computes a fresh guess.
file2¶
| Field | Value |
|---|---|
| Type | string |
| Default | empty |
| Used by | NACME and previous-step workflows |
Path to a second JSON restart file. NACME can use file2 for previous-step
information. If it is omitted, NACME can instead use [input] system2.
save_mol¶
| Field | Value |
|---|---|
| Type | boolean |
| Default | False |
| Used by | restart, orbital export, and inspection workflows |
Requests saving molecular data for later restart or inspection. Supported bases also add portable AO basis, molecular-orbital, vibrational, and state-specific Dyson data for visualization. See Orbital and Vibrational Output.
continue_geom¶
| Field | Value |
|---|---|
| Type | boolean |
| Default | False |
| Used by | JSON restart geometry |
When true, reuses geometry from the JSON restart file. The input checker warns
if continue_geom=true is set without type=json.
swapmo¶
| Field | Value |
|---|---|
| Type | comma-separated integer list |
| Default | empty |
| Used by | manual orbital reordering before SCF |
Swaps molecular orbitals in pairs. The list must contain an even number of indices:
[guess]
swapmo=2,7,8,21
This swaps 2 with 7 and 8 with 21. Use it only when you know the target
orbital ordering.