Notebooks · lib/hf/opts
The Hartree-Fock options, a record with defaults
Every choice a Hartree-Fock run makes lives in one record, ScfOptions.
scf_defaults() returns the production choices, and a caller changes the
ones it wants with a record update:
o = ScfOptions { guess: GS_CORE, max_iter: 200, ..scf_defaults() }| Field | Default | Meaning |
|---|---|---|
| method | SCF_AUTO | SCF_RHF, SCF_UHF, SCF_ROHF; automatic is RHF for a closed shell and UHF otherwise |
| guess | 0 | the starting density: a member of gs_methods() (lib/hf/guess) |
| accelerator | 0 | a member of accel_methods(): DIIS, plain iteration, damping |
| jk | 0 | a member of the J/K registry: packed, pair tables, dense, direct |
| orthogonalizer | 0 | a member of orth_methods() |
| eigensolver | 0 | a member of eig_methods() |
| rohf_coupling | 0 | a member of rohf_couplings() (lib/hf/coupling) |
| diis_size | 8 | Fock matrices DIIS mixes |
| diis_start | 1 | iterations whose Fock matrix DIIS leaves out: 1 leaves out the guess's, as PySCF's diis_start_cycle = 1 does |
| max_iter | 100 | the SCF iteration limit |
| e_tol | 10−12 | the energy change that counts as converged |
| grad_tol | 10−9 | the largest commutator element that counts as converged |
| level_shift | 0 | raise the virtual orbitals by this much (Eh) |
| damping | 0.3 | the damping factor of the damping accelerator |
| lindep | 10−8 | canonical orthogonalization drops overlap eigenvalues at or below this |
| screen_tol | 10−14 | Schwarz screening threshold of the integral builds, in core and direct |
| direct_tol | 10−13 | the direct J/K build skips a shell quartet whose Schwarz bound times the largest density element it meets is at or below this (PySCF's direct_scf_tol) |
| fock_rebuild | 8 | a direct run builds J and K from the change of density, and from the whole density every this many iterations and on every iteration once the convergence test first passes; 0 builds from the whole density every iteration |
| eri_members | 0 | the ERI members the pipeline runs, a bit mask; 0 means MD (generated kernels) and HGP |
| cross_check | 0 | 0: every integral stage runs its production member; 1: every member, asserting they agree |
| stab_hessian | 0 | the Hessian member stability analysis uses (lib/hf/stab) |
Index 0 of every registry is its production member. scf_checked() is the
defaults with cross_check on: the integrals computed by every member and
held to agree within each stage's tolerance, which is how the lock ladder
(scf/) and the library's own tests run. A cross-checked stage asserts
agreement, and an assertion outside a test block prints its verdict, so a
program that cross-checks at its top level prints one line per stage.
The column array. A registry member is called through apply, which
passes numbers, functions and arrays, not records. So the members read their
options from a plain array, opt_array(o, na, nb, enuc), one column per
field plus the electron counts and the nuclear repulsion. The SCF driver
builds it once per run; nothing above the registries builds one by hand, and
the column numbers (OPT_* below) are named in this module only.
opt_new() is the array of the defaults, for a member's own tests.
Used with import hf.opts.
Look inside this program
- Atlas
The program’s map: every function and which calls which.
There’s no recorded run of this program yet.
This program declares a record type (ScfOptions), and records run only in compiled C for now, so the Run buttons here are off. Open it in the workbench and use its C tab to compile it.
Shift+Enter in a cell runs it and moves to the next. Running a cell runs every cell above it too, as one program.