MOPAC Output Files

Using again the AM1 water optimization as an example, the results of the AM1 optimization will be stored in a file with the same name as the input file, but ending in .out. The first part of the ouptut file reminds you of the program version:
 

 *******************************************************************************
 **                      MOPAC (PUBLIC DOMAIN)                                **
 *******************************************************************************

                                 AM1 CALCULATION RESULTS


 *******************************************************************************
 *          MOPAC:  VERSION  7.00               CALC'D. Wed Jun 25 11:12:18 2003
 *   T=      - A TIME OF    48.0 HOURS   REQUESTED
 *  DUMP=N   - RESTART FILE WRITTEN EVERY  3600.0 SECONDS
 *  EF       - USE EF ROUTINE FOR MINIMUM SEARCH
 *  AM1      - THE AM1 HAMILTONIAN TO BE USED
 *  PRECISE  - CRITERIA TO BE INCREASED BY 100 TIMES
 ***********************************************************************040BY040

After this header lines, the keywords are again listed together with various representations of the structure of the system:
 

AM1 PRECISE EF T=48H
 test3 AM1 optimization of water
 

    ATOM   CHEMICAL  BOND LENGTH    BOND ANGLE     TWIST ANGLE
   NUMBER  SYMBOL    (ANGSTROMS)     (DEGREES)      (DEGREES)
    (I)                  NA:I          NB:NA:I      NC:NB:NA:I     NA   NB   NC

      1      O       
      2      H         1.00000  *                                  1
      3      H         1.00000  *     105.00000  *                 1    2


          CARTESIAN COORDINATES 

    NO.       ATOM         X         Y         Z

     1         O         .0000     .0000     .0000
     2         H        1.0000     .0000     .0000
     3         H        -.2588     .9659     .0000


     MOLECULAR POINT GROUP   :   C2V 

The parameters used in the AM1 calculations for the elements O and H are those given in the following two literature citations:
 

  H: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985)          
  O: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985)          

Details pertaining to the geometry optimization are subsequently listed only briefly. In particular there is no information on partially optimized structures. In the current example, the geometry optimization is complete after 7 optimization cycles. At this point both the SCF as well as the geometry optimization criteria are fulfilled.
 

          RHF CALCULATION, NO. OF DOUBLY OCCUPIED LEVELS =  4


            INTERATOMIC DISTANCES
0
                  O  1       H  2       H  3
 ------------------------------------------
     O    1    .000000
     H    2   1.000000    .000000
     H    3   1.000000   1.586707    .000000

          DIAGONAL MATRIX USED AS START HESSIAN

 CYCLE:   1 TIME:    .00 TIME LEFT: 172800.0 GRAD.:    54.071 HEAT:-57.64871    
 CYCLE:   2 TIME:    .00 TIME LEFT: 172800.0 GRAD.:     2.569 HEAT:-59.22653    
 CYCLE:   3 TIME:    .00 TIME LEFT: 172800.0 GRAD.:     1.369 HEAT:-59.23409    
 CYCLE:   4 TIME:    .00 TIME LEFT: 172800.0 GRAD.:     1.111 HEAT:-59.23926    
 CYCLE:   5 TIME:    .00 TIME LEFT: 172800.0 GRAD.:      .371 HEAT:-59.24072    
 CYCLE:   6 TIME:    .00 TIME LEFT: 172800.0 GRAD.:      .051 HEAT:-59.24078    
 CYCLE:   7 TIME:    .00 TIME LEFT: 172800.0 GRAD.:      .001 HEAT:-59.24079    

     RMS GRADIENT =   .00141  IS LESS THAN CUTOFF =   .05000



 -------------------------------------------------------------------------------
 AM1 PRECISE EF T=48H
 test3 AM1 optimization of water
 


     GEOMETRY OPTIMISED USING EIGENVECTOR FOLLOWING (EF).     
     SCF FIELD WAS ACHIEVED                                   


The most important energetic parameters are then listed in the output file together with the overall CPU time needed for the calculation.

                                AM1    CALCULATION
                                                       VERSION  7.00
                                                       Wed Jun 25 11:12:18 2003




          FINAL HEAT OF FORMATION =        -59.24079 KCAL


          TOTAL ENERGY            =       -348.56254 EV
          ELECTRONIC ENERGY       =       -493.26959 EV
          CORE-CORE REPULSION     =        144.70704 EV

          IONIZATION POTENTIAL    =         12.46417
          NO. OF FILLED LEVELS    =          4
          MOLECULAR WEIGHT        =     18.015


          SCF CALCULATIONS  =                8
          COMPUTATION TIME =    .000 SECONDS

The output file then contains the optimized molecular structure
 

    ATOM   CHEMICAL  BOND LENGTH    BOND ANGLE     TWIST ANGLE
   NUMBER  SYMBOL    (ANGSTROMS)     (DEGREES)      (DEGREES)
    (I)                  NA:I          NB:NA:I      NC:NB:NA:I     NA   NB   NC

      1      O       
      2      H          .96127  *                                  1
      3      H          .96127  *     103.53103  *                 1    2


            INTERATOMIC DISTANCES
0
                  O  1       H  2       H  3
 ------------------------------------------
     O    1    .000000
     H    2    .961267    .000000
     H    3    .961267   1.510121    .000000


      MOLECULAR POINT GROUP   :   C2V 


as well as further information on the electronic stucture of the system
 

                  EIGENVALUES

 -36.42411 -18.19965 -14.95262 -12.46417   4.41831   6.19152


              NET ATOMIC CHARGES AND DIPOLE CONTRIBUTIONS

         ATOM NO.   TYPE          CHARGE        ATOM  ELECTRON DENSITY
           1          O           -.3827          6.3827
           2          H            .1914           .8086
           3          H            .1914           .8086
 DIPOLE           X         Y         Z       TOTAL
 POINT-CHG.      .677      .859      .000     1.094
 HYBRID          .475      .602      .000      .767
 SUM            1.151     1.461      .000     1.860
 
           CARTESIAN COORDINATES 

    NO.       ATOM               X         Y         Z

     1         O                   .0000     .0000     .0000
     2         H                   .9613     .0000     .0000
     3         H                  -.2249     .9346     .0000


          ATOMIC ORBITAL ELECTRON POPULATIONS

   1.86274   1.24275   1.27722   2.00000    .80865    .80865



 TOTAL CPU TIME:              .00 SECONDS

The program has finnished successfully if the output file ends in
 


 == MOPAC DONE ==