Element = Lattice = Model = Element: Si
Lattice: hcp
Model: MEAM_LAMMPS_HuangDongLiu_2018_Si__MO_050147023220_002
Computed model cutoff of 5.000000004544876 Angstroms
Computed isolated atomic energy of 0.0 eV for species Si

==============================================================================
==============================================================================
 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: -15.716791
         Iterations: 40
         Function evaluations: 86
Results for this minimization:
  a = 2.9942618370056198, total energy = -15.716790563170632

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: -15.716791
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.994261851906776, total energy = -15.716790563170617

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: -15.716791
         Iterations: 40
         Function evaluations: 84
Results for this minimization:
  a = 2.9942618226632476, total energy = -15.716790563170626

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: -15.716791
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.9942618351429777, total energy = -15.716790563170632

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: -15.716791
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.9942618312314195, total energy = -15.71679056317063

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: -15.716791
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.994261844456198, total energy = -15.716790563170626

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: -15.716791
         Iterations: 37
         Function evaluations: 77
Results for this minimization:
  a = 2.994261842127889, total energy = -15.71679056317063

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: -15.716791
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.994261832209304, total energy = -15.716790563170637

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: -15.716791
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.9942618295550374, total energy = -15.716790563170628

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: -15.716791
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.994261830626057, total energy = -15.716790563170628

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: -15.716791
         Iterations: 37
         Function evaluations: 81
Results for this minimization:
  a = 2.9942618246655917, total energy = -15.71679056317063

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: -15.716791
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.9942618388682596, total energy = -15.716790563170632

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: -15.716791
         Iterations: 36
         Function evaluations: 75
Results for this minimization:
  a = 2.994261835468933, total energy = -15.716790563170632

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: -15.716791
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 2.9942618206143385, total energy = -15.716790563170624

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: -15.716791
         Iterations: 35
         Function evaluations: 73
Results for this minimization:
  a = 2.994261839240791, total energy = -15.71679056317063

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: -15.716791
         Iterations: 33
         Function evaluations: 68
Results for this minimization:
  a = 2.994261833958445, total energy = -15.716790563170637

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: -15.716791
         Iterations: 32
         Function evaluations: 68
Results for this minimization:
  a = 2.9942618253640836, total energy = -15.716790563170626

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: -15.716791
         Iterations: 34
         Function evaluations: 71
Results for this minimization:
  a = 2.994261838175589, total energy = -15.71679056317063

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: -15.716791
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 2.9942618347704406, total energy = -15.716790563170637

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: -15.716791
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 2.9942618294327987, total energy = -15.716790563170628

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: -15.716791
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.994261829415336, total energy = -15.71679056317063

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: -15.716791
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 2.9942618302535253, total energy = -15.716790563170632

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: -15.716791
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 2.9942618383211084, total energy = -15.71679056317063

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: -15.716791
         Iterations: 35
         Function evaluations: 73
Results for this minimization:
  a = 2.9942618358298185, total energy = -15.716790563170632

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: -15.716791
         Iterations: 35
         Function evaluations: 73
Results for this minimization:
  a = 2.994261828064918, total energy = -15.71679056317063

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: -15.716791
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.9942618409055286, total energy = -15.716790563170626

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: -15.716791
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 2.9942618258763085, total energy = -15.716790563170628

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: -15.716791
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.9942618379718624, total energy = -15.716790563170628

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: -15.716791
         Iterations: 38
         Function evaluations: 83
Results for this minimization:
  a = 2.9942618379718593, total energy = -15.71679056317063

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: -15.716791
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 2.994261846691368, total energy = -15.716790563170624

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: -15.716791
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.99426184074837, total energy = -15.71679056317063

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: -15.716791
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.9942618391592957, total energy = -15.716790563170632

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: -15.716791
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.9942618464119732, total energy = -15.716790563170628

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: -15.716791
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.994261840614485, total energy = -15.71679056317063

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


Attempting to perform relaxation using initial lattice constant guess of a = [2.99426183] Angstroms and c = 3.9116872774420566 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 4.156167732282185 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 4.4006481871223135 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 4.645128641962442 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 4.8896090968025705 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 5.134089551642699 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 5.3785700064828275 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 5.623050461322956 = ([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 = 5.125 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 = [2.99426183] Angstroms and c = 5.867530916163084 = ([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 = 5.125 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 = [2.99426183] Angstroms, c = [4.8896091] Angstroms, c/a = 1.632993

 Total energy: -15.716790563170637 eV

 Cohesive energy: -3.929197640792659 eV/atom

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