Element = Lattice = Model = Element: Pb
Lattice: hcp
Model: MEAM_LAMMPS_LeeShimBaskes_2003_Pb__MO_019208265157_001
Computed model cutoff of 5.500000007003557 Angstroms
Computed isolated atomic energy of 0.0 eV for species Pb

==============================================================================
==============================================================================
 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: -8.148076
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 3.5005521804094366, total energy = -8.148075963140853

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: -8.148076
         Iterations: 42
         Function evaluations: 87
Results for this minimization:
  a = 3.5005521990358828, total energy = -8.148075963140856

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: -8.148076
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 3.5005521886632778, total energy = -8.148075963140858

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: -8.148076
         Iterations: 39
         Function evaluations: 82
Results for this minimization:
  a = 3.5005521871149634, total energy = -8.148075963140855

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: -8.148076
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 3.5005521990358877, total energy = -8.148075963140853

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: -8.148076
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 3.500552184507253, total energy = -8.148075963140856

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: -8.148076
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 3.500552186695858, total energy = -8.148075963140856

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: -8.148076
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 3.500552186393179, total energy = -8.148075963140858

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: -8.148076
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 3.5005521892569997, total energy = -8.148075963140856

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: -8.148076
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 3.500552205741407, total energy = -8.148075963140853

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: -8.148076
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 3.500552185624839, total energy = -8.148075963140855

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: -8.148076
         Iterations: 38
         Function evaluations: 83
Results for this minimization:
  a = 3.500552186206912, total energy = -8.148075963140856

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: -8.148076
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 3.5005521886632778, total energy = -8.148075963140858

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: -8.148076
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 3.50055220462382, total energy = -8.148075963140855

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: -8.148076
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 3.5005521891638667, total energy = -8.148075963140858

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: -8.148076
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 3.5005521995248285, total energy = -8.14807596314086

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: -8.148076
         Iterations: 34
         Function evaluations: 71
Results for this minimization:
  a = 3.5005521878600137, total energy = -8.148075963140856

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: -8.148076
         Iterations: 33
         Function evaluations: 70
Results for this minimization:
  a = 3.500552186742425, total energy = -8.148075963140856

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: -8.148076
         Iterations: 33
         Function evaluations: 71
Results for this minimization:
  a = 3.5005521941930065, total energy = -8.148075963140856

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: -8.148076
         Iterations: 32
         Function evaluations: 72
Results for this minimization:
  a = 3.500552205741406, total energy = -8.148075963140853

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: -8.148076
         Iterations: 32
         Function evaluations: 70
Results for this minimization:
  a = 3.5005521863698954, total energy = -8.148075963140855

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: -8.148076
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 3.50055220045615, total energy = -8.148075963140853

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: -8.148076
         Iterations: 33
         Function evaluations: 69
Results for this minimization:
  a = 3.5005521825514734, total energy = -8.148075963140856

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: -8.148076
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.5005521971965194, total energy = -8.148075963140856

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: -8.148076
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.5005521882325406, total energy = -8.148075963140856

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: -8.148076
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 3.5005522035062313, total energy = -8.148075963140855

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: -8.148076
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 3.5005522057414042, total energy = -8.148075963140853

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: -8.148076
         Iterations: 36
         Function evaluations: 75
Results for this minimization:
  a = 3.500552188488655, total energy = -8.148075963140856

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: -8.148076
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 3.500552177242933, total energy = -8.148075963140856

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: -8.148076
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 3.5005522064864625, total energy = -8.148075963140853

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: -8.148076
         Iterations: 37
         Function evaluations: 82
Results for this minimization:
  a = 3.5005521848797803, total energy = -8.148075963140855

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: -8.148076
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 3.500552197219802, total energy = -8.148075963140858

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: -8.148076
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 3.50055218860507, total energy = -8.148075963140856

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: -8.148076
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 3.5005521884479056, total energy = -8.148075963140856

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: -8.148076
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 3.50055219704518, total energy = -8.148075963140855

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: -8.148076
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 3.5005521892569975, total energy = -8.148075963140855

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: -8.148076
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 3.500552187114952, total energy = -8.148075963140855

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: -8.148076
         Iterations: 38
         Function evaluations: 79
Results for this minimization:
  a = 3.500552175566554, total energy = -8.148075963140855

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


Attempting to perform relaxation using initial lattice constant guess of a = [3.5005522] Angstroms and c = 4.573102243633686 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 4.858921133860791 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 5.144740024087897 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 5.430558914315002 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 5.716377804542107 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 6.0021966947692125 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 6.288015584996318 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 6.573834475223423 = ([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 = 5.625 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 = [3.5005522] Angstroms and c = 6.859653365450528 = ([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 = 5.625 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 = [3.5005522] Angstroms, c = [5.7163778] Angstroms, c/a = 1.632993

 Total energy: -8.14807596314086 eV

 Cohesive energy: -2.037018990785215 eV/atom

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