Element = Lattice = Model = Element: Sn
Lattice: hcp
Model: MEAM_LAMMPS_VellaChenStillinger_2017_Sn__MO_316045643888_002
Computed model cutoff of 4.79999999620023 Angstroms
Computed isolated atomic energy of 0.0 eV for species Sn

==============================================================================
==============================================================================
 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: -12.239583
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 3.3896815776824996, total energy = -12.239583390423023

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: -12.239583
         Iterations: 41
         Function evaluations: 86
Results for this minimization:
  a = 3.389681573957205, total energy = -12.239583390423022

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: -12.239583
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 3.3896815702319145, total energy = -12.239583390423022

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: -12.239583
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 3.3896815709769816, total energy = -12.239583390423018

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: -12.239583
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 3.3896815896034282, total energy = -12.239583390423023

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: -12.239583
         Iterations: 39
         Function evaluations: 86
Results for this minimization:
  a = 3.389681580185427, total energy = -12.23958339042303

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: -12.239583
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 3.389681579917669, total energy = -12.239583390423018

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: -12.239583
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 3.389681562781334, total energy = -12.239583390423025

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: -12.239583
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 3.3896815776824987, total energy = -12.239583390423023

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: -12.239583
         Iterations: 36
         Function evaluations: 75
Results for this minimization:
  a = 3.3896815776824973, total energy = -12.23958339042302

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: -12.239583
         Iterations: 41
         Function evaluations: 87
Results for this minimization:
  a = 3.3896815890446303, total energy = -12.239583390423023

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: -12.239583
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 3.389681570976969, total energy = -12.23958339042302

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: -12.239583
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 3.389681577682495, total energy = -12.239583390423027

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: -12.239583
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 3.3896815892891032, total energy = -12.239583390423022

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: -12.239583
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 3.3896815679036116, total energy = -12.239583390423022

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: -12.239583
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.389681581780315, total energy = -12.23958339042302

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: -12.239583
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 3.3896815871587025, total energy = -12.23958339042302

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: -12.239583
         Iterations: 33
         Function evaluations: 71
Results for this minimization:
  a = 3.389681577536976, total energy = -12.239583390423025

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: -12.239583
         Iterations: 32
         Function evaluations: 68
Results for this minimization:
  a = 3.389681579731405, total energy = -12.239583390423022

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: -12.239583
         Iterations: 32
         Function evaluations: 69
Results for this minimization:
  a = 3.3896815739572053, total energy = -12.239583390423022

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: -12.239583
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 3.3896815799176685, total energy = -12.23958339042302

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: -12.239583
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.389681596681475, total energy = -12.239583390423023

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: -12.239583
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 3.3896815683692694, total energy = -12.239583390423022

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: -12.239583
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.3896815866697567, total energy = -12.23958339042302

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: -12.239583
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 3.389681583642959, total energy = -12.239583390423023

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: -12.239583
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 3.389681583526545, total energy = -12.239583390423027

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: -12.239583
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 3.389681577682494, total energy = -12.239583390423025

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: -12.239583
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 3.3896815720945597, total energy = -12.239583390423025

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: -12.239583
         Iterations: 36
         Function evaluations: 74
Results for this minimization:
  a = 3.3896815840154857, total energy = -12.239583390423022

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: -12.239583
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 3.389681571256368, total energy = -12.239583390423018

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: -12.239583
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 3.3896815708663786, total energy = -12.239583390423022

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: -12.239583
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 3.389681562781332, total energy = -12.239583390423018

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


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 4.428261473048149 = ([1.30639453] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 4.705027815113659 = ([1.38804419] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 4.981794157179168 = ([1.46969385] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 5.258560499244678 = ([1.5513435] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 5.535326841310187 = ([1.63299316] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 5.812093183375697 = ([1.71464282] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 6.088859525441206 = ([1.79629248] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 6.365625867506716 = ([1.87794214] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = [3.38968158] Angstroms and c = 6.642392209572225 = ([1.95959179] * a) Angstroms

     Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 4.875 Angstroms
     Exception message:
setting an array element with a sequence. The requested array has an inhomogeneous shape after 1 dimensions. The detected shape was (2,) + inhomogeneous part.
     Continuing...


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

 Final lattice Constants:
   a = [3.38968158] Angstroms, c = [5.53532684] Angstroms, c/a = 1.632993

 Total energy: -12.23958339042303 eV

 Cohesive energy: -3.0598958476057576 eV/atom

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