Element = Lattice = Model = Element: Cu
Lattice: hcp
Model: LJ_ElliottAkerson_2015_Universal__MO_959249795837_003
Computed model cutoff of 9.40788999497892 Angstroms
Computed isolated atomic energy of 0.0 eV for species Cu

==============================================================================
==============================================================================
 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: -68.103166
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.567580955103043, total energy = -68.10316570456024

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: -68.103166
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.56758096262347, total energy = -68.10316570456031

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: -68.103166
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809671520256, total energy = -68.10316570456064

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: -68.103166
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809461623484, total energy = -68.10316570456001

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: -68.103166
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.5675809681415585, total energy = -68.1031657045603

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: -68.103166
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.5675809893757124, total energy = -68.1031657045602

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: -68.103166
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.5675809530541307, total energy = -68.10316570456004

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: -68.103166
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.5675809625536203, total energy = -68.10316570456031

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: -68.103166
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 2.5675809971988217, total energy = -68.10316570456058

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: -68.103166
         Iterations: 35
         Function evaluations: 77
Results for this minimization:
  a = 2.567580946884118, total energy = -68.10316570456011

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: -68.103166
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 2.56758096262347, total energy = -68.10316570456028

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: -68.103166
         Iterations: 34
         Function evaluations: 76
Results for this minimization:
  a = 2.5675809999578627, total energy = -68.10316570455983

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: -68.103166
         Iterations: 33
         Function evaluations: 72
Results for this minimization:
  a = 2.5675809671520256, total energy = -68.10316570456057

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: -68.103166
         Iterations: 33
         Function evaluations: 71
Results for this minimization:
  a = 2.5675809530541303, total energy = -68.10316570456

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: -68.103166
         Iterations: 33
         Function evaluations: 72
Results for this minimization:
  a = 2.567580946162343, total energy = -68.10316570455994

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: -68.103166
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 2.5675809893757098, total energy = -68.10316570456018

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: -68.103166
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 2.567580968141555, total energy = -68.10316570456027

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: -68.103166
         Iterations: 36
         Function evaluations: 79
Results for this minimization:
  a = 2.567580947652459, total energy = -68.10316570456017

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: -68.103166
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 2.5675809893757107, total energy = -68.10316570456024

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: -68.103166
         Iterations: 36
         Function evaluations: 75
Results for this minimization:
  a = 2.567580958327743, total energy = -68.10316570456041

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: -68.103166
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.567580947838722, total energy = -68.10316570456003

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: -68.103166
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.5675809871405337, total energy = -68.10316570456024

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: -68.103166
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.5675809625536203, total energy = -68.10316570456033

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: -68.103166
         Iterations: 37
         Function evaluations: 77
Results for this minimization:
  a = 2.5675809884502057, total energy = -68.1031657045601

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: -68.103166
         Iterations: 37
         Function evaluations: 77
Results for this minimization:
  a = 2.567580997198819, total energy = -68.10316570456061

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: -68.103166
         Iterations: 37
         Function evaluations: 81
Results for this minimization:
  a = 2.5675809871405377, total energy = -68.1031657045603

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: -68.103166
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809468841146, total energy = -68.10316570456017

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: -68.103166
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809520762414, total energy = -68.10316570456001

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: -68.103166
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809626234654, total energy = -68.10316570456024

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: -68.103166
         Iterations: 38
         Function evaluations: 83
Results for this minimization:
  a = 2.567580945260122, total energy = -68.10316570455994

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: -68.103166
         Iterations: 39
         Function evaluations: 85
Results for this minimization:
  a = 2.5675810001790538, total energy = -68.10316570455988

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: -68.103166
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.567580956686285, total energy = -68.10316570456015

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: -68.103166
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.5675809671520256, total energy = -68.10316570456054

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: -68.103166
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.567580959154288, total energy = -68.10316570456061

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: -68.103166
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809550099062, total energy = -68.10316570456008

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: -68.103166
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.567580990988065, total energy = -68.10316570456027

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: -68.103166
         Iterations: 39
         Function evaluations: 81
Results for this minimization:
  a = 2.567580962553617, total energy = -68.10316570456028

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: -68.103166
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 2.5675809611566365, total energy = -68.10316570456014

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: -68.103166
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.5675809933920335, total energy = -68.10316570456015

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: -68.103166
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809617619945, total energy = -68.10316570456015

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: -68.103166
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.5675809687003412, total energy = -68.10316570456023

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: -68.103166
         Iterations: 40
         Function evaluations: 85
Results for this minimization:
  a = 2.567580953054126, total energy = -68.10316570456001

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: -68.103166
         Iterations: 40
         Function evaluations: 87
Results for this minimization:
  a = 2.567580947652459, total energy = -68.10316570456018

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: -68.103166
         Iterations: 40
         Function evaluations: 85
Results for this minimization:
  a = 2.5675809524254856, total energy = -68.10316570456006

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: -68.103166
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 2.567580986878595, total energy = -68.10316570456014

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: -68.103166
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.567580968455869, total energy = -68.10316570456037

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: -68.103166
         Iterations: 40
         Function evaluations: 83
Results for this minimization:
  a = 2.5675809583277394, total energy = -68.1031657045604

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: -68.103166
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.5675809623935493, total energy = -68.10316570456038

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: -68.103166
         Iterations: 41
         Function evaluations: 86
Results for this minimization:
  a = 2.5675809478387217, total energy = -68.10316570455998

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: -68.103166
         Iterations: 40
         Function evaluations: 83
Results for this minimization:
  a = 2.5675809608073843, total energy = -68.10316570456023

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

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 2.5675809871405266, total energy = -68.10316570456027

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

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.5675809520936994, total energy = -68.1031657045603

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

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 41
         Function evaluations: 89
Results for this minimization:
  a = 2.5675809625536203, total energy = -68.10316570456033

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

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.5675809613341745, total energy = -68.10316570456071

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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 9.40788999497892 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 = 9.0 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 = 9.0 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.9000000000000234 Angstroms and c = -1.469693845669945 Angstroms; the model cutoff was estimated to be 9.40788999497892 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 = 9.125 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 = 9.125 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.9125000000000156 Angstroms and c = -1.4901062601931256 Angstroms; the model cutoff was estimated to be 9.40788999497892 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 = 9.25 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 = 9.25 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.9250000000000078 Angstroms and c = -1.510518674716306 Angstroms; the model cutoff was estimated to be 9.40788999497892 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 = 9.375 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 = 9.375 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.9375 Angstroms and c = -1.5309310892394863 Angstroms; the model cutoff was estimated to be 9.40788999497892 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 = 9.5 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 = 9.5 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.9499999999999922 Angstroms and c = -1.5513435037626666 Angstroms; the model cutoff was estimated to be 9.40788999497892 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...


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 Starting optimization with both a and c/a relaxed
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Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 3.354273721895164 = ([1.30639453] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 71
         Function evaluations: 156
Results for this minimization:
  a = 2.5675638912643617, c = 4.192897963587322, total energy = -68.1031658218793

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 3.5639158295136117 = ([1.38804419] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 71
         Function evaluations: 151
Results for this minimization:
  a = 2.567563878092125, c = 4.192897926092811, total energy = -68.10316582187953

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 3.7735579371320593 = ([1.46969385] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 77
         Function evaluations: 163
Results for this minimization:
  a = 2.5675638642237977, c = 4.192897899503711, total energy = -68.10316582187907

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 3.983200044750507 = ([1.5513435] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 72
         Function evaluations: 150
Results for this minimization:
  a = 2.567563881787122, c = 4.19289792844725, total energy = -68.10316582187933

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 4.1928421523689545 = ([1.63299316] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 64
         Function evaluations: 137
Results for this minimization:
  a = 2.567563895715458, c = 4.192897940928538, total energy = -68.10316582187933

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 4.402484259987402 = ([1.71464282] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 75
         Function evaluations: 150
Results for this minimization:
  a = 2.567563882913264, c = 4.192897948825829, total energy = -68.10316582187927

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 4.61212636760585 = ([1.79629248] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 77
         Function evaluations: 159
Results for this minimization:
  a = 2.567563913499046, c = 4.192897885899105, total energy = -68.10316582187917

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 4.821768475224298 = ([1.87794214] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 72
         Function evaluations: 156
Results for this minimization:
  a = 2.5675639000912858, c = 4.192897948114652, total energy = -68.10316582187934

Attempting to perform relaxation using initial lattice constant guess of a = [2.56758096] Angstroms and c = 5.031410582842745 = ([1.95959179] * a) Angstroms

Optimization terminated successfully.
         Current function value: -68.103166
         Iterations: 76
         Function evaluations: 165
Results for this minimization:
  a = 2.56756389743554, c = 4.1928979335640975, total energy = -68.1031658218794

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 Finished with optimization
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 Final lattice Constants:
   a = 2.567563878092125 Angstroms, c = 4.192897926092811 Angstroms, c/a = 1.633026

 Total energy: -68.10316582187953 eV

 Cohesive energy: -17.025791455469882 eV/atom

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