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All results from a given calculation for C8H6 (benzocyclobutadiene)

using model chemistry: MP2/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at MP2/3-21G*
 hartrees
Energy at 0K-305.304939
Energy at 298.15K-305.310071
HF Energy-304.604855
Nuclear repulsion energy308.326969
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 MP2/3-21G*
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 3280 3120 10.91      
2 A1 3220 3063 11.24      
3 A1 3201 3046 8.01      
4 A1 1645 1565 1.50      
5 A1 1478 1406 4.96      
6 A1 1447 1376 0.49      
7 A1 1428 1359 11.02      
8 A1 1242 1182 0.02      
9 A1 1093 1040 0.06      
10 A1 1056 1005 0.02      
11 A1 948 902 1.47      
12 A1 782 744 0.21      
13 A1 543 516 0.01      
14 A2 909 864 0.00      
15 A2 863 821 0.00      
16 A2 787 749 0.00      
17 A2 578 550 0.00      
18 A2 429 408 0.00      
19 A2 287 273 0.00      
20 B1 867 825 6.36      
21 B1 738 702 88.92      
22 B1 650 618 51.15      
23 B1 346 329 0.45      
24 B1 184 175 12.56      
25 B2 3248 3090 1.49      
26 B2 3211 3055 20.70      
27 B2 3188 3033 0.01      
28 B2 1611 1533 0.94      
29 B2 1480 1408 5.72      
30 B2 1340 1275 0.04      
31 B2 1269 1207 15.21      
32 B2 1098 1044 1.53      
33 B2 1061 1009 1.92      
34 B2 842 801 0.04      
35 B2 671 639 0.90      
36 B2 383 364 3.44      

Unscaled Zero Point Vibrational Energy (zpe) 23700.2 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 22546.0 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 MP2/3-21G*
ABC
0.15782 0.07091 0.04893

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 1.458 -0.631
C2 0.000 0.693 -1.869
C3 0.000 -0.693 -1.869
C4 0.000 -1.458 -0.631
C5 0.000 -0.688 2.079
C6 0.000 0.688 2.079
C7 0.000 0.731 0.526
C8 0.000 -0.731 0.526
H9 0.000 2.545 -0.662
H10 0.000 1.232 -2.813
H11 0.000 -1.232 -2.813
H12 0.000 -2.545 -0.662
H13 0.000 -1.455 2.841
H14 0.000 1.455 2.841

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 C7 C8 H9 H10 H11 H12 H13 H14
C11.45522.48192.91593.45582.81661.36632.47571.08732.19413.46404.00284.53153.4715
C21.45521.38622.48194.18173.94722.39512.78622.21021.08742.14443.45555.17624.7707
C32.48191.38621.45523.94724.18172.78622.39513.45552.14441.08742.21024.77075.1762
C42.91592.48191.45522.81663.45582.47571.36634.00283.46402.19411.08733.47154.5315
C53.45584.18173.94722.81661.37512.10281.55304.23775.25484.92183.31061.08152.2737
C62.81663.94724.18173.45581.37511.55302.10283.31064.92185.25484.23772.27371.0815
C71.36632.39512.78622.47572.10281.55301.46172.16843.37663.87343.48453.18352.4253
C82.47572.78622.39511.36631.55302.10281.46173.48453.87343.37662.16842.42533.1835
H91.08732.21023.45554.00284.23773.31062.16843.48452.51994.34655.08965.31653.6686
H102.19411.08742.14443.46405.25484.92183.37663.87342.51992.46434.34656.25985.6583
H113.46402.14441.08742.19414.92185.25483.87343.37664.34652.46432.51995.65836.2598
H124.00283.45552.21021.08733.31064.23773.48452.16845.08964.34652.51993.66865.3165
H134.53155.17624.77073.47151.08152.27373.18352.42535.31656.25985.65833.66862.9092
H143.47154.77075.17624.53152.27371.08152.42533.18353.66865.65836.25985.31652.9092

picture of benzocyclobutadiene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 121.706 C1 C2 H10 118.577
C1 C7 C6 149.448 C1 C7 N8 122.151
C2 C1 C7 116.143 C2 C1 H9 120.054
C2 C3 C4 121.706 C2 C3 H11 119.717
C3 C2 H10 119.717 C3 C4 N8 116.143
C3 C4 H12 120.054 C4 C3 H11 118.577
C4 N8 C5 149.448 C4 N8 C7 122.151
C5 C6 C7 91.599 C5 C6 H14 135.176
C5 N8 C7 88.401 C6 C5 N8 91.599
C6 C5 H13 135.176 C6 C7 N8 88.401
C7 C1 H9 123.803 C7 C6 H14 133.225
N8 C4 H12 123.803 N8 C5 H13 133.225
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability