Element = Lattice = Model = Element: Nb
Lattice: hcp
Model: MEAM_LAMMPS_YangQi_2019_Nb__MO_360068930164_000
Computed model cutoff of 5.2499999675154845 Angstroms
Computed isolated atomic energy of 0.0 eV for species Nb

==============================================================================
==============================================================================
 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: -26.730156
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.9788767099380533, total energy = -26.730156193043495

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: -26.730156
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.97887672802899, total energy = -26.730156193043513

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: -26.730156
         Iterations: 39
         Function evaluations: 84
Results for this minimization:
  a = 2.9788767099380493, total energy = -26.730156193043513

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: -26.730156
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 2.9788767650723527, total energy = -26.730156193043506

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: -26.730156
         Iterations: 38
         Function evaluations: 81
Results for this minimization:
  a = 2.978876709938053, total energy = -26.7301561930435

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: -26.730156
         Iterations: 40
         Function evaluations: 87
Results for this minimization:
  a = 2.978876769100318, total energy = -26.7301561930435

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: -26.730156
         Iterations: 39
         Function evaluations: 83
Results for this minimization:
  a = 2.978876788914204, total energy = -26.730156193043438

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: -26.730156
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.9788767099380493, total energy = -26.730156193043513

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: -26.730156
         Iterations: 36
         Function evaluations: 79
Results for this minimization:
  a = 2.9788767099380524, total energy = -26.7301561930435

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: -26.730156
         Iterations: 36
         Function evaluations: 79
Results for this minimization:
  a = 2.97887671327917, total energy = -26.7301561930435

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: -26.730156
         Iterations: 37
         Function evaluations: 79
Results for this minimization:
  a = 2.978876725514419, total energy = -26.73015619304351

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: -26.730156
         Iterations: 35
         Function evaluations: 78
Results for this minimization:
  a = 2.978876709938048, total energy = -26.730156193043495

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: -26.730156
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 2.9788767099380493, total energy = -26.73015619304351

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: -26.730156
         Iterations: 35
         Function evaluations: 78
Results for this minimization:
  a = 2.978876737249083, total energy = -26.730156193043484

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: -26.730156
         Iterations: 33
         Function evaluations: 71
Results for this minimization:
  a = 2.9788767671212555, total energy = -26.73015619304348

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: -26.730156
         Iterations: 33
         Function evaluations: 73
Results for this minimization:
  a = 2.9788767550140633, total energy = -26.73015619304348

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: -26.730156
         Iterations: 32
         Function evaluations: 69
Results for this minimization:
  a = 2.9788767099380493, total energy = -26.73015619304349

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: -26.730156
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.9788767697755247, total energy = -26.730156193043484

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: -26.730156
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.978876725514418, total energy = -26.73015619304352

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: -26.730156
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.9788767805206593, total energy = -26.730156193043452

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: -26.730156
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.978876799182034, total energy = -26.730156193043435

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: -26.730156
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.978876792622031, total energy = -26.730156193043474

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: -26.730156
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.9788767102872953, total energy = -26.730156193043502

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: -26.730156
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.9788767409510886, total energy = -26.730156193043502

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: -26.730156
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.9788767099380484, total energy = -26.730156193043502

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: -26.730156
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.978876757068793, total energy = -26.730156193043467

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: -26.730156
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 2.9788767166435695, total energy = -26.73015619304347

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: -26.730156
         Iterations: 37
         Function evaluations: 81
Results for this minimization:
  a = 2.9788767993450165, total energy = -26.73015619304342

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: -26.730156
         Iterations: 37
         Function evaluations: 80
Results for this minimization:
  a = 2.9788767280289874, total energy = -26.73015619304349

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: 0.000000
         Iterations: 35
         Function evaluations: 102
Results for this minimization:
  a = 5.318750000000001, total energy = 0.0

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: 0.000000
         Iterations: 35
         Function evaluations: 102
Results for this minimization:
  a = 5.462499999999999, total energy = 0.0

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: 0.000000
         Iterations: 34
         Function evaluations: 99
Results for this minimization:
  a = 5.362500000000001, total energy = 0.0

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: -0.000000
         Iterations: 36
         Function evaluations: 99
Results for this minimization:
  a = 5.249999999650754, total energy = -4.412095384323275e-17

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: 0.000000
         Iterations: 33
         Function evaluations: 97
Results for this minimization:
  a = 5.3812500000000005, total energy = 0.0

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: -0.000000
         Iterations: 35
         Function evaluations: 99
Results for this minimization:
  a = 5.249999999511056, total energy = -4.5166312430024267e-17

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


Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 3.8915882582203243 = ([1.30639453] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 84
         Function evaluations: 177
Results for this minimization:
  a = 2.8502572462054534, c = 5.339820396891782, total energy = -26.828183914929497

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 4.134812524359095 = ([1.38804419] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 77
         Function evaluations: 164
Results for this minimization:
  a = 2.850257192846924, c = 5.339820695644814, total energy = -26.82818391492948

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 4.378036790497866 = ([1.46969385] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 73
         Function evaluations: 157
Results for this minimization:
  a = 2.850257190178298, c = 5.339820686343325, total energy = -26.828183914929486

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 4.621261056636636 = ([1.5513435] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 74
         Function evaluations: 160
Results for this minimization:
  a = 2.8502572019707175, c = 5.339820557196393, total energy = -26.828183914929525

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 4.864485322775407 = ([1.63299316] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 72
         Function evaluations: 151
Results for this minimization:
  a = 2.8502572099320953, c = 5.339820403783191, total energy = -26.8281839149295

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 5.107709588914178 = ([1.71464282] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 67
         Function evaluations: 143
Results for this minimization:
  a = 2.850257174675785, c = 5.33982055640069, total energy = -26.828183914929514

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 5.350933855052949 = ([1.79629248] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 67
         Function evaluations: 145
Results for this minimization:
  a = 2.8502571802905514, c = 5.339820571324632, total energy = -26.8281839149295

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 5.594158121191719 = ([1.87794214] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 66
         Function evaluations: 148
Results for this minimization:
  a = 2.8502572015305945, c = 5.339820400245856, total energy = -26.8281839149295

Attempting to perform relaxation using initial lattice constant guess of a = [2.97887673] Angstroms and c = 5.837382387330489 = ([1.95959179] * a) Angstroms

Optimization terminated successfully.
         Current function value: -26.828184
         Iterations: 77
         Function evaluations: 162
Results for this minimization:
  a = 2.850257206799356, c = 5.33982045307598, total energy = -26.828183914929525

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

 Final lattice Constants:
   a = 2.8502572019707175 Angstroms, c = 5.339820557196393 Angstroms, c/a = 1.873452

 Total energy: -26.828183914929525 eV

 Cohesive energy: -6.707045978732381 eV/atom

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