Element = Lattice = Model = Element: Ni
Lattice: hcp
Model: LJ_ElliottAkerson_2015_Universal__MO_959249795837_003
Computed model cutoff of 8.837719995006944 Angstroms
Computed isolated atomic energy of 0.0 eV for species Ni

==============================================================================
==============================================================================
 Starting optimization to find optimum lattice constant 'a' with c/a fixed to
 sqrt(8/3)
==============================================================================
==============================================================================


Attempting to perform relaxation using initial lattice constant guess of a = 1.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.4119739655405312, total energy = -69.13871345285669

Attempting to perform relaxation using initial lattice constant guess of a = 1.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.4119739823043345, total energy = -69.13871345285683

Attempting to perform relaxation using initial lattice constant guess of a = 1.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.4119739904417656, total energy = -69.13871345285703

Attempting to perform relaxation using initial lattice constant guess of a = 1.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 2.4119739733636427, total energy = -69.13871345285705

Attempting to perform relaxation using initial lattice constant guess of a = 1.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.4119739565998346, total energy = -69.13871345285696

Attempting to perform relaxation using initial lattice constant guess of a = 1.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 37
         Function evaluations: 77
Results for this minimization:
  a = 2.4119739793473878, total energy = -69.1387134528567

Attempting to perform relaxation using initial lattice constant guess of a = 1.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.4119739600457253, total energy = -69.13871345285679

Attempting to perform relaxation using initial lattice constant guess of a = 1.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 2.411973964422941, total energy = -69.13871345285695

Attempting to perform relaxation using initial lattice constant guess of a = 2.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 2.411973953247071, total energy = -69.13871345285666

Attempting to perform relaxation using initial lattice constant guess of a = 2.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 33
         Function evaluations: 70
Results for this minimization:
  a = 2.4119739644229417, total energy = -69.13871345285693

Attempting to perform relaxation using initial lattice constant guess of a = 2.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 32
         Function evaluations: 68
Results for this minimization:
  a = 2.4119739824091093, total energy = -69.1387134528568

Attempting to perform relaxation using initial lattice constant guess of a = 2.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 32
         Function evaluations: 69
Results for this minimization:
  a = 2.411973984260112, total energy = -69.13871345285705

Attempting to perform relaxation using initial lattice constant guess of a = 2.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 33
         Function evaluations: 71
Results for this minimization:
  a = 2.4119739830493927, total energy = -69.13871345285685

Attempting to perform relaxation using initial lattice constant guess of a = 2.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 2.4119739944755563, total energy = -69.13871345285688

Attempting to perform relaxation using initial lattice constant guess of a = 2.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 34
         Function evaluations: 71
Results for this minimization:
  a = 2.4119739733636374, total energy = -69.1387134528571

Attempting to perform relaxation using initial lattice constant guess of a = 2.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.4119739733636374, total energy = -69.1387134528571

Attempting to perform relaxation using initial lattice constant guess of a = 3.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.4119739543646563, total energy = -69.13871345285672

Attempting to perform relaxation using initial lattice constant guess of a = 3.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.4119739595334977, total energy = -69.13871345285682

Attempting to perform relaxation using initial lattice constant guess of a = 3.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 2.4119739794230552, total energy = -69.13871345285666

Attempting to perform relaxation using initial lattice constant guess of a = 3.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.411973982461494, total energy = -69.13871345285688

Attempting to perform relaxation using initial lattice constant guess of a = 3.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 75
Results for this minimization:
  a = 2.411973962164483, total energy = -69.13871345285682

Attempting to perform relaxation using initial lattice constant guess of a = 3.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.4119739830493905, total energy = -69.13871345285692

Attempting to perform relaxation using initial lattice constant guess of a = 3.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.411973964422941, total energy = -69.13871345285696

Attempting to perform relaxation using initial lattice constant guess of a = 3.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 37
         Function evaluations: 77
Results for this minimization:
  a = 2.411973967053923, total energy = -69.13871345285682

Attempting to perform relaxation using initial lattice constant guess of a = 4.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.4119739644229394, total energy = -69.13871345285692

Attempting to perform relaxation using initial lattice constant guess of a = 4.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.4119739733636396, total energy = -69.13871345285716

Attempting to perform relaxation using initial lattice constant guess of a = 4.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.411973964422938, total energy = -69.13871345285695

Attempting to perform relaxation using initial lattice constant guess of a = 4.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.4119739605957875, total energy = -69.13871345285689

Attempting to perform relaxation using initial lattice constant guess of a = 4.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.411973982409104, total energy = -69.13871345285685

Attempting to perform relaxation using initial lattice constant guess of a = 4.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.4119739858055245, total energy = -69.13871345285679

Attempting to perform relaxation using initial lattice constant guess of a = 4.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.4119739842601136, total energy = -69.13871345285705

Attempting to perform relaxation using initial lattice constant guess of a = 4.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.411973961489272, total energy = -69.1387134528569

Attempting to perform relaxation using initial lattice constant guess of a = 5.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.4119739830493927, total energy = -69.13871345285679

Attempting to perform relaxation using initial lattice constant guess of a = 5.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 84
Results for this minimization:
  a = 2.411973964422936, total energy = -69.13871345285696

Attempting to perform relaxation using initial lattice constant guess of a = 5.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 40
         Function evaluations: 85
Results for this minimization:
  a = 2.4119739944755545, total energy = -69.13871345285685

Attempting to perform relaxation using initial lattice constant guess of a = 5.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.4119739733636405, total energy = -69.13871345285712

Attempting to perform relaxation using initial lattice constant guess of a = 5.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.411973973363634, total energy = -69.138713452857

Attempting to perform relaxation using initial lattice constant guess of a = 5.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 81
Results for this minimization:
  a = 2.4119739742891397, total energy = -69.13871345285706

Attempting to perform relaxation using initial lattice constant guess of a = 5.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.411973973363632, total energy = -69.138713452857

Attempting to perform relaxation using initial lattice constant guess of a = 5.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.4119739824905966, total energy = -69.13871345285693

Attempting to perform relaxation using initial lattice constant guess of a = 6.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.411973982304327, total energy = -69.13871345285692

Attempting to perform relaxation using initial lattice constant guess of a = 6.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.411973994597789, total energy = -69.13871345285675

Attempting to perform relaxation using initial lattice constant guess of a = 6.25 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 40
         Function evaluations: 85
Results for this minimization:
  a = 2.4119739595334977, total energy = -69.13871345285682

Attempting to perform relaxation using initial lattice constant guess of a = 6.375 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.4119739644229394, total energy = -69.13871345285695

Attempting to perform relaxation using initial lattice constant guess of a = 6.5 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 41
         Function evaluations: 86
Results for this minimization:
  a = 2.411973971780383, total energy = -69.13871345285696

Attempting to perform relaxation using initial lattice constant guess of a = 6.625 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 43
         Function evaluations: 95
Results for this minimization:
  a = 2.411973971311809, total energy = -69.13871345285683

Attempting to perform relaxation using initial lattice constant guess of a = 6.75 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.41197398230433, total energy = -69.13871345285695

Attempting to perform relaxation using initial lattice constant guess of a = 6.875 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 41
         Function evaluations: 88
Results for this minimization:
  a = 2.411974008195102, total energy = -69.13871345285636

Attempting to perform relaxation using initial lattice constant guess of a = 7.0 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 40
         Function evaluations: 83
Results for this minimization:
  a = 2.4119739621644825, total energy = -69.13871345285683

Attempting to perform relaxation using initial lattice constant guess of a = 7.125 Angstroms (c/a fixed at sqrt(8/3))

Optimization terminated successfully.
         Current function value: -69.138713
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.4119739590445466, total energy = -69.13871345285668

Attempting to perform relaxation using initial lattice constant guess of a = 7.25 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.25 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.7250000000000156 Angstroms and c = -1.1839200423452283 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 7.375 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.375 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.7375000000000078 Angstroms and c = -1.2043324568684086 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 7.5 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.5 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.75 Angstroms and c = -1.224744871391589 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 7.625 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.625 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.7624999999999922 Angstroms and c = -1.2451572859147695 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 7.75 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.75 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.7750000000000234 Angstroms and c = -1.2655697004380135 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 7.875 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 7.875 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.7875000000000156 Angstroms and c = -1.285982114961194 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.0 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.0 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8000000000000078 Angstroms and c = -1.3063945294843744 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.125 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.125 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8125 Angstroms and c = -1.3268069440075547 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.25 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.25 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8249999999999922 Angstroms and c = -1.3472193585307353 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.375 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.375 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8375000000000234 Angstroms and c = -1.3676317730539793 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.5 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.5 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8500000000000156 Angstroms and c = -1.3880441875771599 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.625 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.625 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8625000000000078 Angstroms and c = -1.4084566021003402 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.75 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.75 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.875 Angstroms and c = -1.4288690166235205 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 8.875 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 8.875 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.8874999999999922 Angstroms and c = -1.449281431146701 Angstroms; the model cutoff was estimated to be 8.837719995006944 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


==============================================================================
==============================================================================
 Starting optimization with both a and c/a relaxed
==============================================================================
==============================================================================


Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 3.150989604060918 = ([1.30639453] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 72
         Function evaluations: 154
Results for this minimization:
  a = 2.411957919375503, c = 3.93878936610671, total energy = -69.13871357195961

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 3.3479264543147256 = ([1.38804419] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 72
         Function evaluations: 155
Results for this minimization:
  a = 2.4119579344636444, c = 3.938789408489474, total energy = -69.13871357195971

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 3.544863304568533 = ([1.46969385] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 71
         Function evaluations: 151
Results for this minimization:
  a = 2.411957944858087, c = 3.938789371754927, total energy = -69.13871357195966

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 3.7418001548223403 = ([1.5513435] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 67
         Function evaluations: 144
Results for this minimization:
  a = 2.4119579399462294, c = 3.938789424310777, total energy = -69.13871357195978

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 3.9387370050761477 = ([1.63299316] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 69
         Function evaluations: 148
Results for this minimization:
  a = 2.411957946338743, c = 3.9387893541233465, total energy = -69.13871357195985

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 4.135673855329955 = ([1.71464282] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 73
         Function evaluations: 151
Results for this minimization:
  a = 2.4119579303569556, c = 3.938789394937632, total energy = -69.13871357195984

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 4.332610705583763 = ([1.79629248] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 75
         Function evaluations: 161
Results for this minimization:
  a = 2.411957917680665, c = 3.9387893971225, total energy = -69.1387135719598

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 4.52954755583757 = ([1.87794214] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 71
         Function evaluations: 149
Results for this minimization:
  a = 2.411957930479585, c = 3.9387893260248257, total energy = -69.13871357195964

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 4.726484406091377 = ([1.95959179] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 78
         Function evaluations: 161
Results for this minimization:
  a = 2.4119579440932304, c = 3.938789367361953, total energy = -69.13871357195983

Attempting to perform relaxation using initial lattice constant guess of a = [2.41197397] Angstroms and c = 4.9234212563451845 = ([2.04124145] * a) Angstroms

Optimization terminated successfully.
         Current function value: -69.138714
         Iterations: 70
         Function evaluations: 151
Results for this minimization:
  a = 2.4119579426006377, c = 3.938789327896302, total energy = -69.13871357195978

==============================================================================
==============================================================================
 Finished with optimization
==============================================================================
==============================================================================

 Final lattice Constants:
   a = 2.411957946338743 Angstroms, c = 3.9387893541233465 Angstroms, c/a = 1.633026

 Total energy: -69.13871357195985 eV

 Cohesive energy: -17.284678392989964 eV/atom

==============================================================================
==============================================================================