Element = Lattice = Model = Element: N
Lattice: hcp
Model: Sim_LAMMPS_ExTeP_LosKroesAlbe_2017_BN__SM_692329995993_001
Computed model cutoff of 2.2000000012293843 Angstroms
Computed isolated atomic energy of 0.0 eV for species N

==============================================================================
==============================================================================
 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: -6.548560
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.0537615597248107, total energy = -6.548560283814732

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: -6.548560
         Iterations: 40
         Function evaluations: 85
Results for this minimization:
  a = 2.0537615682464097, total energy = -6.548560283814707

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: -6.548560
         Iterations: 38
         Function evaluations: 82
Results for this minimization:
  a = 2.053761564195156, total energy = -6.548560283814725

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: -6.548560
         Iterations: 36
         Function evaluations: 77
Results for this minimization:
  a = 2.0537615641951588, total energy = -6.548560283814721

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: -6.548560
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 2.053761563077571, total energy = -6.548560283814731

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: -6.548560
         Iterations: 35
         Function evaluations: 72
Results for this minimization:
  a = 2.053761559893611, total energy = -6.548560283814731

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: -6.548560
         Iterations: 33
         Function evaluations: 69
Results for this minimization:
  a = 2.0537615653127435, total energy = -6.548560283814732

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: -6.548560
         Iterations: 32
         Function evaluations: 68
Results for this minimization:
  a = 2.0537615627981722, total energy = -6.548560283814724

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: -6.548560
         Iterations: 31
         Function evaluations: 65
Results for this minimization:
  a = 2.053761562891305, total energy = -6.548560283814691

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: -6.548560
         Iterations: 33
         Function evaluations: 70
Results for this minimization:
  a = 2.053761560376733, total energy = -6.548560283814716

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: -6.548560
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 2.0537615590263156, total energy = -6.548560283814725

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 2.375, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 2.5, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 2.625, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 2.75, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 2.875, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 3.0, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 3.125, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 3.25, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 3.375, total energy = 0.0

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: 0.000000
         Iterations: 32
         Function evaluations: 95
Results for this minimization:
  a = 3.5, total energy = 0.0

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


Attempting to perform relaxation using initial lattice constant guess of a = [2.05376156] Angstroms and c = 2.683022866489763 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 2.850711795645373 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.0184007248009834 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.1860896539565937 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.353778583112204 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.5214675122678143 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.6891564414234246 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 3.856845370579035 = ([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 = 3.5 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 = [2.05376156] Angstroms and c = 4.024534299734645 = ([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 = 3.5 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 = [2.05376156] Angstroms, c = [3.35377858] Angstroms, c/a = 1.632993

 Total energy: -6.548560283814732 eV

 Cohesive energy: -1.637140070953683 eV/atom

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