| Eχ = Dμνfμνχ + IμνSμνχ + Γ(μνλσ)<μν||λσ>χ |
Gradients in serial ACESII
1. DENS
Calculate one and two-particle density matrix elements and store them
on disk
Calculate I(pq) and X(pq) intermediates and store them on disk
2. ANTI
Re-sort density matrix to Mulliken order
3. BCKTRN
Back-transform density matrix to AO basis
4. VDINT
Calculate two-electron integral derivatives and contract them with
two-particle AO density matrix.
Calculate one-electron integral derivatives and contract them with
one-particle AO density matrix.
Calculate AO overlap matrix derivatives and contract them with
I(pq) and X(pq) intermediates.
Parallel ACESII gradients
From VCC and LAMBDA we get converged half-transformed
t(i,μ),
t(ij,μν)
and
λ(μ,i),
λ(μν,ij).
Instead of creating and storing two-particle density matrix, we
calculate one-particle normal and energy-weighed density matrices,
D(pq) and I(pq).
Another two-index quantity which needs to be calculated
in Phase I is the X(pq) global intermediate (GI),
which is used to iteratively
solve for the occupied-virtual part of D.
I(pq) and X(pq) intermediates expressed
in terms of Γ and W
Phase I (direct integrals):
Storage :
Phase II (direct integral derivatives):