Aromatic Hydrocarbons: Benzene

In Kimball.exe there are two types of nodes with double bonds to choose from: Localized and delocalizable p-bonds. The first type is e.g. present in ethene or in the CO-bond of formaldehyde. The latter are appropriate for aromatic and other conjugated systems with partial or total equalization of C-C bondlengths. Here we show the results for Benzene:

Benzene - Energies
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                                 Kimball     Gamess/6-31g  Gamess/Sto-3g  Sto-3g/opt
Nucleus-Nucleus      Vnn      :  200.7545     200.754628    200.754628    205.018026
Electron-Electron    Vee      :  269.4826     276.384687    277.864247    282.188167
Nucleus-Electron     Vne      : -928.7216    -938.153579   -932.294879   -942.998812
Electron potential   Vel      : -659.239     -661.768892   -654.430632   -660.810645
Electronic energy    Eel      : -430.0059    -431.374222   -428.637960   -432.913568

potential energy     V        : -458.4845    -461.014264   -453.676005   -455.791930
kinetic   energy     T        :  229.2331     230.394669    225.792672    227.896387

total     energy     Etot     : -229.2514    -230.619594   -227.883332   -227.895543

Virial ratio        -V/T      :    2.00008     2.000976       2.009259      1.9999963

Benzene - Interatomic Distances and Angles from Kimball

CC                   : 1.419736 Å              same           same          1.3836 Å
CH                   : 1.073511 Å                                           1.0796 Å
CCC                  : 120. deg

Benzene - Cartesian Coordinates from Kimball
    used by Gamess
C   0.529177    0.9165615  -1.071527E-11
C   1.239045   -0.3129663  -1.071527E-11
C   0.529177   -1.542494   -1.132554E-12
C  -0.8905593  -1.542494    8.450162E-12
C  -1.600428   -0.3129663   1.803288E-11
C  -0.8905593   0.9165615   1.803288E-11
H   1.065932    1.846249   -1.071527E-11
H   2.312556   -0.3129663  -1.796109E-11
H   1.065932   -2.472182   -1.132554E-12
H  -1.427315   -2.472182    8.450162E-12
H  -2.673938   -0.3129663   2.527869E-11
H  -1.427315    1.846249    2.527869E-11
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