Result of calculation

The result, obtained with the symmetry input file is:
 AM1 T=3600 SYMMETRY NOINTER NOXYZ
  z-matrix for cyclohexane
  with symmetry
  Xx    0.000000  0    0.000000  0    0.000000  0    0   0   0
  Xx    0.457253  1    0.000000  0    0.000000  0    1   0   0
  C     1.444513  1   90.000000  0    0.000000  0    1   2   0   -0.1547
  C     1.444513  0   90.000000  0  120.000000  0    1   2   3   -0.1547
  C     1.444513  0   90.000000  0 -120.000000  0    1   2   3   -0.1547
  C     1.444513  0   90.000000  0   60.000000  0    2   1   5   -0.1547
  C     1.444513  0   90.000000  0  120.000000  0    2   1   6   -0.1547
  C     1.444513  0   90.000000  0 -120.000000  0    2   1   6   -0.1547
  H     1.121756  1   93.712534  1  180.000000  0    3   1   2    0.0778
  H     1.121756  0   93.712534  0  180.000000  0    4   1   2    0.0778
  H     1.121756  0   93.712534  0  180.000000  0    5   1   2    0.0778
  H     1.121756  0   93.712534  0  180.000000  0    6   2   1    0.0778
  H     1.121756  0   93.712534  0  180.000000  0    7   2   1    0.0778
  H     1.121756  0   93.712534  0  180.000000  0    8   2   1    0.0778
  H     1.120981  1  158.802518  1    0.000000  0    3   1   2    0.0768
  H     1.120981  0  158.802518  0    0.000000  0    4   1   2    0.0768
  H     1.120981  0  158.802518  0    0.000000  0    5   1   2    0.0768
  H     1.120981  0  158.802518  0    0.000000  0    6   2   1    0.0768
  H     1.120981  0  158.802518  0    0.000000  0    7   2   1    0.0768
  H     1.120981  0  158.802518  0    0.000000  0    8   2   1    0.0768
  0     0.000000  0    0.000000  0    0.000000  0    0   0   0

COMPUTATION TIME        =       4.50 SECONDS
HEAT OF FORMATION       =     -38.542260 KCAL
This corresponds to We should compare this result to the alternative: full minimization of a crude, sketched structure, without symmetry constraints, but with the keyword PRECISE added:
 AM1 T=3599 PRECISE NOINTER NOXYZ
  crude structure for full minimization
  
  C     0.000000  0    0.000000  0    0.000000  0    0   0   0   -0.1547
  H     1.120901  1    0.000000  0    0.000000  0    1   0   0    0.0768
  H     1.121776  1  107.480005  1    0.000000  0    1   2   0    0.0779
  C     1.515263  1  109.585075  1  118.805558  1    1   2   3   -0.1548
  H     1.121754  1  109.429201  1   55.712766  1    4   1   2    0.0779
  H     1.120909  1  109.588733  1  -61.902294  1    4   1   2    0.0768
  C     1.515284  1  111.278204  1  176.710219  1    4   1   2   -0.1547
  H     1.121792  1  109.399660  1   65.652727  1    7   4   1    0.0780
  H     1.120810  1  109.595293  1 -176.689331  1    7   4   1    0.0768
  C     1.515331  1  111.248342  1  -55.337575  1    7   4   1   -0.1547
  H     1.120904  1  109.595833  1  176.653225  1   10   7   4    0.0768
  H     1.121715  1  109.408839  1  -65.703316  1   10   7   4    0.0780
  C     1.515216  1  111.254367  1   55.325878  1   10   7   4   -0.1548
  H     1.121792  1  109.416680  1   65.707530  1   13  10   7    0.0779
  H     1.120816  1  109.593667  1 -176.694655  1   13  10   7    0.0768
  C     1.515373  1  111.295889  1  -55.307812  1   13  10   7   -0.1547
  H     1.120868  1  109.574772  1  176.639184  1   16  13  10    0.0768
  H     1.121737  1  109.409963  1  -65.752008  1   16  13  10    0.0779
  0     0.000000  0    0.000000  0    0.000000  0    0   0   0
COMPUTATION TIME        =      12.12 SECONDS
HEAT OF FORMATION       =     -38.541855 KCAL
We notice that: The final conclusion is a matter of discussion, principle and taste:
Back to Chapter 1, section D.