Element = Lattice = Model = Element: Si
Lattice: hcp
Model: SNAP_ZuoChenLi_2019quadratic_Si__MO_721469752060_000
Computed model cutoff of 4.799999978169825 Angstroms
Computed isolated atomic energy of -3.1609571201530056 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))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.0 Angstroms
Exception message:
Attempted to evaluate energy at a = 0.2999999999999994 Angstroms and c = 0.4898979485566346 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.125 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.125 Angstroms
Exception message:
Attempted to evaluate energy at a = 0.33749999999999813 Angstroms and c = 0.551135192126212 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.25 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.25 Angstroms
Exception message:
Attempted to evaluate energy at a = 0.375 Angstroms and c = 0.6123724356957945 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.375 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.375 Angstroms
Exception message:
Attempted to evaluate energy at a = 0.41249999999999876 Angstroms and c = 0.673609679265372 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.5 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.5 Angstroms
Exception message:
Attempted to evaluate energy at a = 0.4499999999999975 Angstroms and c = 0.7348469228349493 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.625 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.625 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.1625000000000032 Angstroms and c = -0.26536138880151616 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


Attempting to perform relaxation using initial lattice constant guess of a = 1.75 Angstroms (c/a fixed at sqrt(8/3))

Failed to perform relaxation w.r.t. 'a' with c/a fixed at sqrt(8/3) and an initial guess of a = 1.75 Angstroms
Exception message:
Attempted to evaluate energy at a = -0.1750000000000007 Angstroms and c = -0.28577380332470526 Angstroms; the model cutoff was estimated to be 4.799999978169825 Angstroms.  This may mean that the model does not possess close-range repulsive forces to prevent system collapse.  In order to prevent possible neighbor list overflow, both a and c must be greater than 0.1 times the model cutoff...
Continuing...


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: -6.274277
         Iterations: 36
         Function evaluations: 80
Results for this minimization:
  a = 2.815350517630577, total energy = -6.2742770051899726

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: -6.274277
         Iterations: 36
         Function evaluations: 78
Results for this minimization:
  a = 2.815350562147797, total energy = -6.2742770051900045

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: -6.274277
         Iterations: 37
         Function evaluations: 78
Results for this minimization:
  a = 2.8153505475551377, total energy = -6.27427700518998

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: -6.274277
         Iterations: 35
         Function evaluations: 76
Results for this minimization:
  a = 2.8153505578637126, total energy = -6.274277005189994

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: -6.274277
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 2.815350560017394, total energy = -6.274277005189994

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: -6.274277
         Iterations: 34
         Function evaluations: 73
Results for this minimization:
  a = 2.8153505884110928, total energy = -6.274277005189987

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: -6.274277
         Iterations: 33
         Function evaluations: 73
Results for this minimization:
  a = 2.8153505911119274, total energy = -6.274277005189983

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: -6.274277
         Iterations: 33
         Function evaluations: 73
Results for this minimization:
  a = 2.8153505863621833, total energy = -6.2742770051899726

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: -6.274277
         Iterations: 32
         Function evaluations: 70
Results for this minimization:
  a = 2.815350541338557, total energy = -6.274277005190001

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: -6.274277
         Iterations: 34
         Function evaluations: 75
Results for this minimization:
  a = 2.8153505634516467, total energy = -6.27427700518998

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: -6.274277
         Iterations: 34
         Function evaluations: 72
Results for this minimization:
  a = 2.815350560704246, total energy = -6.274277005189983

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: -6.274277
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 2.8153505826019676, total energy = -6.274277005189987

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: -6.274277
         Iterations: 36
         Function evaluations: 76
Results for this minimization:
  a = 2.815350570960435, total energy = -6.274277005189997

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: -6.274277
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 2.8153505656868214, total energy = -6.27427700518998

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: -6.274277
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 2.8153505552560074, total energy = -6.274277005189994

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: -6.274277
         Iterations: 35
         Function evaluations: 77
Results for this minimization:
  a = 2.815350517630577, total energy = -6.274277005189962

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: -0.049257
         Iterations: 38
         Function evaluations: 80
Results for this minimization:
  a = 4.595102056581526, total energy = -0.04925687563925507

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: -0.049257
         Iterations: 36
         Function evaluations: 79
Results for this minimization:
  a = 4.595102129876615, total energy = -0.04925687563923731

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: -0.049257
         Iterations: 33
         Function evaluations: 72
Results for this minimization:
  a = 4.595102033496367, total energy = -0.04925687563924619

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: -0.049257
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 4.595102117955685, total energy = -0.049256875639233755

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: -0.049257
         Iterations: 33
         Function evaluations: 69
Results for this minimization:
  a = 4.595102079038043, total energy = -0.04925687563924441

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: -0.049257
         Iterations: 35
         Function evaluations: 75
Results for this minimization:
  a = 4.595102038979533, total energy = -0.04925687563924086

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: -0.049257
         Iterations: 34
         Function evaluations: 74
Results for this minimization:
  a = 4.595102078700437, total energy = -0.04925687563924086

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: -0.049257
         Iterations: 34
         Function evaluations: 76
Results for this minimization:
  a = 4.595101996045559, total energy = -0.049256875639208886

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: -0.049257
         Iterations: 35
         Function evaluations: 74
Results for this minimization:
  a = 4.595102082146332, total energy = -0.04925687563924086

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


Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 3.677958572970605 = ([1.30639453] * a) Angstroms

Optimization terminated successfully.
         Current function value: -6.949635
         Iterations: 75
         Function evaluations: 161
Results for this minimization:
  a = 3.569357867357351, c = 3.2080926627724056, total energy = -6.949634932881892

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 3.9078309837812677 = ([1.38804419] * a) Angstroms

Optimization terminated successfully.
         Current function value: -7.571671
         Iterations: 75
         Function evaluations: 166
Results for this minimization:
  a = 3.979360306112359, c = 2.4826166310427267, total energy = -7.57167112488402

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 4.137703394591931 = ([1.46969385] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 74
         Function evaluations: 157
Results for this minimization:
  a = 2.3762138581379046, c = 5.458907799451797, total energy = -8.807911005793787

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 4.367575805402593 = ([1.5513435] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 73
         Function evaluations: 151
Results for this minimization:
  a = 2.3762138440290412, c = 5.458907797995715, total energy = -8.80791100579378

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 4.597448216213255 = ([1.63299316] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 72
         Function evaluations: 157
Results for this minimization:
  a = 2.3762138479164596, c = 5.458907772625613, total energy = -8.807911005793798

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 4.827320627023918 = ([1.71464282] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 72
         Function evaluations: 156
Results for this minimization:
  a = 2.3762138648338436, c = 5.458907739423504, total energy = -8.807911005793795

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 5.0571930378345815 = ([1.79629248] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 74
         Function evaluations: 160
Results for this minimization:
  a = 2.3762138433522413, c = 5.4589078506263755, total energy = -8.807911005793802

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 5.287065448645244 = ([1.87794214] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 70
         Function evaluations: 149
Results for this minimization:
  a = 2.376213857841405, c = 5.458907775738551, total energy = -8.807911005793773

Attempting to perform relaxation using initial lattice constant guess of a = [2.81535056] Angstroms and c = 5.516937859455906 = ([1.95959179] * a) Angstroms

Optimization terminated successfully.
         Current function value: -8.807911
         Iterations: 71
         Function evaluations: 155
Results for this minimization:
  a = 2.37621384492817, c = 5.458907823256911, total energy = -8.807911005793812

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

 Final lattice Constants:
   a = 2.37621384492817 Angstroms, c = 5.458907823256911 Angstroms, c/a = 2.297313

 Total energy: -8.807911005793812 eV

 Cohesive energy: -2.201977751448453 eV/atom

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