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All results from a given calculation for C8H6 (benzocyclobutadiene)

using model chemistry: CISD/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at CISD/3-21G
 hartrees
Energy at 0K-305.204490
Energy at 298.15K-305.210255
HF Energy-304.610188
Nuclear repulsion energy311.097449
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CISD/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A1 3366 3169 9.72      
2 A1 3297 3103 9.75      
3 A1 3277 3085 11.91      
4 A1 1756 1653 1.98      
5 A1 1614 1519 1.42      
6 A1 1518 1429 0.17      
7 A1 1492 1404 18.32      
8 A1 1282 1207 0.06      
9 A1 1136 1070 0.00      
10 A1 1101 1037 0.04      
11 A1 950 894 1.88      
12 A1 824 776 0.20      
13 A1 567 534 0.04      
14 A2 1015 956 0.00      
15 A2 940 885 0.00      
16 A2 916 862 0.00      
17 A2 696 655 0.00      
18 A2 592 558 0.00      
19 A2 309 290 0.00      
20 B1 963 906 11.24      
21 B1 798 751 119.61      
22 B1 748 704 26.69      
23 B1 374 352 2.22      
24 B1 232 219 15.40      
25 B2 3332 3136 0.23      
26 B2 3288 3095 20.07      
27 B2 3261 3070 0.34      
28 B2 1731 1629 0.03      
29 B2 1532 1442 8.06      
30 B2 1390 1308 0.20      
31 B2 1321 1243 13.24      
32 B2 1130 1063 2.73      
33 B2 1101 1036 0.73      
34 B2 900 848 0.02      
35 B2 700 659 0.50      
36 B2 412 388 4.36      

Unscaled Zero Point Vibrational Energy (zpe) 24929.9 cm-1
Scaled (by 0.9413) Zero Point Vibrational Energy (zpe) 23466.5 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at CISD/3-21G
ABC
0.16094 0.07212 0.04980

See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 1.444 -0.622
C2 0.000 0.683 -1.856
C3 0.000 -0.683 -1.856
C4 0.000 -1.444 -0.622
C5 0.000 -0.676 2.063
C6 0.000 0.676 2.063
C7 0.000 0.723 0.518
C8 0.000 -0.723 0.518
H9 0.000 2.523 -0.650
H10 0.000 1.218 -2.794
H11 0.000 -1.218 -2.794
H12 0.000 -2.523 -0.650
H13 0.000 -1.437 2.821
H14 0.000 1.437 2.821

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 C7 C8 H9 H10 H11 H12 H13 H14
C11.44932.45842.88703.42082.79291.34812.44831.07962.18353.43523.96644.48883.4430
C21.44931.36592.45844.14793.91902.37372.75882.19981.08002.11983.42505.13464.7371
C32.45841.36591.44933.91904.14792.75882.37373.42502.11981.08002.19984.73715.1346
C42.88702.45841.44932.79293.42082.44831.34813.96643.43522.18351.07963.44304.4888
C53.42084.14793.91902.79291.35152.08481.54644.19435.21324.88733.28221.07392.2442
C62.79293.91904.14793.42081.35151.54642.08483.28224.88735.21324.19432.24421.0739
C71.34812.37372.75882.44832.08481.54641.44682.14503.34823.83863.44973.15772.4112
C82.44832.75882.37371.34811.54642.08481.44683.44973.83863.34822.14502.41123.1577
H91.07962.19983.42503.96644.19433.28222.14503.44972.50974.31165.04555.26543.6368
H102.18351.08002.11983.43525.21324.88733.34823.83862.50972.43604.31166.21075.6190
H113.43522.11981.08002.18354.88735.21323.83863.34824.31162.43602.50975.61906.2107
H123.96643.42502.19981.07963.28224.19433.44972.14505.04554.31162.50973.63685.2654
H134.48885.13464.73713.44301.07392.24423.15772.41125.26546.21075.61903.63682.8735
H143.44304.73715.13464.48882.24421.07392.41123.15773.63685.61906.21075.26542.8735

picture of benzocyclobutadiene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 121.652 C1 C2 H10 118.649
C1 C7 C6 149.480 C1 C7 N8 122.287
C2 C1 C7 116.061 C2 C1 H9 120.171
C2 C3 C4 121.652 C2 C3 H11 119.699
C3 C2 H10 119.699 C3 C4 N8 116.061
C3 C4 H12 120.171 C4 C3 H11 118.649
C4 N8 C5 149.480 C4 N8 C7 122.287
C5 C6 C7 91.766 C5 C6 H14 135.125
C5 N8 C7 88.234 C6 C5 N8 91.766
C6 C5 H13 135.125 C6 C7 N8 88.234
C7 C1 H9 123.769 C7 C6 H14 133.109
N8 C4 H12 123.769 N8 C5 H13 133.109
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability