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All results from a given calculation for C8H6 (benzocyclobutadiene)

using model chemistry: QCISD/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 QCISD/3-21G*
 hartrees
Energy at 0K-305.360082
Energy at 298.15K-305.365358
HF Energy-304.604442
Nuclear repulsion energy307.955301
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 QCISD/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 3240 3114 12.07      
2 A1 3175 3051 10.54      
3 A1 3156 3034 12.30      
4 A1 1665 1600 1.04      
5 A1 1493 1435 3.96      
6 A1 1446 1389 0.62      
7 A1 1419 1364 11.21      
8 A1 1235 1187 0.04      
9 A1 1084 1042 0.03      
10 A1 1043 1002 0.03      
11 A1 898 863 1.09      
12 A1 782 752 0.10      
13 A1 539 518 0.02      
14 A2 929 893 0.00      
15 A2 870 836 0.00      
16 A2 807 775 0.00      
17 A2 600 577 0.00      
18 A2 529 509 0.00      
19 A2 288 277 0.00      
20 B1 882 848 9.22      
21 B1 743 714 89.07      
22 B1 673 647 37.35      
23 B1 345 331 0.90      
24 B1 207 199 13.25      
25 B2 3209 3084 0.97      
26 B2 3168 3044 22.71      
27 B2 3141 3018 0.38      
28 B2 1641 1578 0.02      
29 B2 1469 1412 6.43      
30 B2 1336 1284 0.04      
31 B2 1261 1212 11.57      
32 B2 1080 1038 1.99      
33 B2 1051 1010 0.50      
34 B2 856 823 0.00      
35 B2 669 643 0.49      
36 B2 387 372 3.53      

Unscaled Zero Point Vibrational Energy (zpe) 23658.2 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 22737.9 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 QCISD/3-21G*
ABC
0.15736 0.07080 0.04883

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 1.460 -0.628
C2 0.000 0.691 -1.872
C3 0.000 -0.691 -1.872
C4 0.000 -1.460 -0.628
C5 0.000 -0.688 2.080
C6 0.000 0.688 2.080
C7 0.000 0.733 0.526
C8 0.000 -0.733 0.526
H9 0.000 2.550 -0.659
H10 0.000 1.233 -2.819
H11 0.000 -1.233 -2.819
H12 0.000 -2.550 -0.659
H13 0.000 -1.458 2.843
H14 0.000 1.458 2.843

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 C7 C8 H9 H10 H11 H12 H13 H14
C11.46212.48492.91923.45622.81611.36352.47801.09042.20293.47114.00934.53423.4707
C21.46211.38292.48494.18603.95232.39842.78932.21921.09082.14453.46075.18164.7767
C32.48491.38291.46213.95234.18602.78932.39843.46072.14451.09082.21924.77675.1816
C42.91922.48491.46212.81613.45622.47801.36354.00933.47112.20291.09043.47074.5342
C53.45624.18603.95232.81611.37522.10581.55494.24045.26224.92963.31191.08402.2772
C62.81613.95234.18603.45621.37521.55492.10583.31194.92965.26224.24042.27721.0840
C71.36352.39842.78932.47802.10581.55491.46652.16853.38223.88003.49003.18892.4275
C82.47802.78932.39841.36351.55492.10581.46653.49003.88003.38222.16852.42753.1889
H91.09042.21923.46074.00934.24043.31192.16853.49002.53034.35575.09915.32173.6675
H102.20291.09082.14453.47115.26224.92963.38223.88002.53032.46514.35576.26875.6663
H113.47112.14451.09082.20294.92965.26223.88003.38224.35572.46512.53035.66636.2687
H124.00933.46072.21921.09043.31194.24043.49002.16855.09914.35572.53033.66755.3217
H134.53425.18164.77673.47071.08402.27723.18892.42755.32176.26875.66633.66752.9163
H143.47074.77675.18164.53422.27721.08402.42753.18893.66755.66636.26875.32172.9163

picture of benzocyclobutadiene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 121.694 C1 C2 H10 118.567
C1 C7 C6 149.495 C1 C7 N8 122.188
C2 C1 C7 116.118 C2 C1 H9 120.082
C2 C3 C4 121.694 C2 C3 H11 119.739
C3 C2 H10 119.739 C3 C4 N8 116.118
C3 C4 H12 120.082 C4 C3 H11 118.567
C4 N8 C5 149.495 C4 N8 C7 122.188
C5 C6 C7 91.683 C5 C6 H14 135.303
C5 N8 C7 88.317 C6 C5 N8 91.683
C6 C5 H13 135.303 C6 C7 N8 88.317
C7 C1 H9 123.799 C7 C6 H14 133.014
N8 C4 H12 123.799 N8 C5 H13 133.014
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability