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[<bmeredig@gmail.com>]

Hi all,

Hunted around here for a while but couldn't find exactly what I'm looking
for--apologies in advance if this is a very simple question.

I ran a BFGS minimization of a cell, which converged after 9 steps. The code
printed

At Broyd/MD step   9, gradients are converged :
  max grad (force/stress) = 3.5201E-04 < tolmxf= 5.0000E-04 ha/bohr (free
atoms)

I was under the impression that the convergence criterion (here 3.5201E-04)
ought to relate to the largest single Cartesian force component on any of the
atoms, or the largest stress component multiplied by strfact (the default,
100). Yet my forces are

cartesian forces (hartree/bohr) at end:
    1      0.00000022196000    -0.00000026184815    -0.00000036891432
    2      0.00000014872891    -0.00000019322115     0.00000038078365
    3      0.00004108870399     0.00007711205062     0.00000161583881
    4     -0.00004129394759    -0.00007690312473    -0.00000162123890
    5     -0.00005079422183    -0.00008924105679     0.00000990463720
    6      0.00005062877651     0.00008948720020    -0.00000991110645
 frms,max,avg= 4.5074698E-05 8.9487200E-05  -1.466E-08  1.384E-08 -4.976E-10
h/b

and my stresses are

 Cartesian components of stress tensor (hartree/bohr^3)
  sigma(1 1)=  2.33910376E-05  sigma(3 2)=  3.67303937E-06
  sigma(2 2)=  1.91354379E-05  sigma(3 1)=  1.59285145E-06
  sigma(3 3)= -5.30868121E-05  sigma(2 1)= -5.32246843E-05

Could someone kindly explain the origin of the 3.5201E-04 that caused the code
to reach convergence?

Thanks much,
Bryce