Minor clean-up

[bhourahine]

Avoids division by undefined volume when not periodic, and moves the documentation

[bhourahine]

@vanderhe unfortunately a little fast with the merging, I just also fixed the REKS cases in the PR (and rebased it on main).

[bhourahine]

REKS changes are
src/dftbp/dftb/hybridxc.F90
@@ -5791,15 +6017,209 @@ contains
end do
end do loopForceAtom

REMOVE:
if (this%tREKS) then
gradients(:,:) = gradients + tmpGradients
else
gradients(:,:) = gradients + 0.5_dp * nSpin * tmpGradients

ADD

if (.not.this%tREKS) then
  tmpGradients(:,:) = 0.5_dp * nSpin * tmpGradients
 end if

src/dftbp/reks/reksinterface.F90
@@ -942,7 +942,7 @@ module dftbp_reks_reksinterface
uncomments block and :
#:else
call hybridXc%addCamGradients_real(env, this%deltaRhoSqrL(:,:,:,iL), this%overSqr,&
& skOverCont, orb, denseDesc%iAtomStart, neighbourList%iNeighbour, nNeighbourSK,&

REMOVE
& nonSccDeriv, .false., lcDerivs(:,:,iL), symNeighbourList=symNeighbourList,&
ADD
& nonSccDeriv, 1.0_dp, .false., lcDerivs(:,:,iL), symNeighbourList=symNeighbourList,&

         & nNeighbourCamSym=nNeighbourCamSym)
     @:PROPAGATE_ERROR(errStatus)

Which is a little hacky as it has to pass a dummy cell volume in, event though non-periodic.

[vanderhe]

REKS changes are src/dftbp/dftb/hybridxc.F90 @@ -5791,15 +6017,209 @@ contains end do end do loopForceAtom

REMOVE: if (this%tREKS) then gradients(:,:) = gradients + tmpGradients else gradients(:,:) = gradients + 0.5_dp * nSpin * tmpGradients

ADD

if (.not.this%tREKS) then
  tmpGradients(:,:) = 0.5_dp * nSpin * tmpGradients
 end if

src/dftbp/reks/reksinterface.F90 @@ -942,7 +942,7 @@ module dftbp_reks_reksinterface uncomments block and : #:else call hybridXc%addCamGradients_real(env, this%deltaRhoSqrL(:,:,:,iL), this%overSqr,& & skOverCont, orb, denseDesc%iAtomStart, neighbourList%iNeighbour, nNeighbourSK,&

REMOVE & nonSccDeriv, .false., lcDerivs(:,:,iL), symNeighbourList=symNeighbourList,& ADD & nonSccDeriv, 1.0_dp, .false., lcDerivs(:,:,iL), symNeighbourList=symNeighbourList,&

         & nNeighbourCamSym=nNeighbourCamSym)
     @:PROPAGATE_ERROR(errStatus)

Which is a little hacky as it has to pass a dummy cell volume in, event though non-periodic.

@bhourahine Applied in dftbplus#1643.

[bhourahine]

Still some failing MPI tests (compile and run), so shall I just force push to your branch once they are fixed, or are you changing things as well?

[vanderhe]

Still some failing MPI tests (compile and run), so shall I just force push to your branch once they are fixed, or are you changing things as well?

I'm going to lunch now, so feel free to force push 😉