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All results from a given calculation for C8H6 (benzocyclobutadiene)

using model chemistry: PBE1PBE/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 PBE1PBE/3-21G
 hartrees
Energy at 0K-306.284753
Energy at 298.15K-306.290503
HF Energy-306.284753
Nuclear repulsion energy311.386219
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 PBE1PBE/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 3315 3184 7.22      
2 A1 3245 3116 5.52      
3 A1 3227 3100 9.75      
4 A1 1715 1647 2.45      
5 A1 1565 1503 0.50      
6 A1 1502 1443 0.19      
7 A1 1455 1397 18.00      
8 A1 1237 1188 0.00      
9 A1 1097 1054 0.48      
10 A1 1083 1040 0.30      
11 A1 983 944 2.82      
12 A1 811 779 0.22      
13 A1 558 536 0.03      
14 A2 1015 975 0.00      
15 A2 955 917 0.00      
16 A2 913 877 0.00      
17 A2 797 766 0.00      
18 A2 599 575 0.00      
19 A2 304 292 0.00      
20 B1 955 917 11.37      
21 B1 774 743 151.27      
22 B1 742 713 0.58      
23 B1 377 362 4.74      
24 B1 235 225 16.39      
25 B2 3281 3151 0.01      
26 B2 3239 3110 14.24      
27 B2 3213 3085 0.29      
28 B2 1671 1605 0.14      
29 B2 1487 1428 8.29      
30 B2 1340 1287 0.76      
31 B2 1268 1218 15.29      
32 B2 1115 1071 2.16      
33 B2 1076 1033 1.51      
34 B2 880 845 0.05      
35 B2 678 651 0.48      
36 B2 409 393 4.85      

Unscaled Zero Point Vibrational Energy (zpe) 24558.7 cm-1
Scaled (by 0.9604) Zero Point Vibrational Energy (zpe) 23586.2 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 PBE1PBE/3-21G
ABC
0.16081 0.07247 0.04996

See section I.F.4 to change rotational constant units
Geometric Data calculated at PBE1PBE/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 1.443 -0.623
C2 0.000 0.685 -1.851
C3 0.000 -0.685 -1.851
C4 0.000 -1.443 -0.623
C5 0.000 -0.678 2.057
C6 0.000 0.678 2.057
C7 0.000 0.722 0.522
C8 0.000 -0.722 0.522
H9 0.000 2.527 -0.653
H10 0.000 1.224 -2.792
H11 0.000 -1.224 -2.792
H12 0.000 -2.527 -0.653
H13 0.000 -1.445 2.815
H14 0.000 1.445 2.815

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 C7 C8 H9 H10 H11 H12 H13 H14
C11.44292.45732.88663.41822.78721.35322.44911.08392.18043.43783.97024.49023.4381
C21.44291.37052.45734.13903.90792.37282.75842.19711.08462.12843.42835.12914.7273
C32.45731.37051.44293.90794.13902.75842.37283.42832.12841.08462.19714.72735.1291
C42.88662.45731.44292.78723.41822.44911.35323.97023.43782.18041.08393.43814.4902
C53.41824.13903.90792.78721.35642.07781.53604.19695.20904.88003.28021.07812.2543
C62.78723.90794.13903.41821.35641.53602.07783.28024.88005.20904.19692.25431.0781
C71.35322.37282.75842.44912.07781.53601.44362.15343.35183.84293.45433.15502.4046
C82.44912.75842.37281.35321.53602.07781.44363.45433.84293.35182.15342.40463.1550
H91.08392.19713.42833.97024.19693.28022.15343.45432.50544.31795.05375.27253.6324
H102.18041.08462.12843.43785.20904.88003.35183.84292.50542.44724.31796.21005.6117
H113.43782.12841.08462.18044.88005.20903.84293.35184.31792.44722.50545.61176.2100
H123.97023.42832.19711.08393.28024.19693.45432.15345.05374.31792.50543.63245.2725
H134.49025.12914.72733.43811.07812.25433.15502.40465.27256.21005.61173.63242.8899
H143.43814.72735.12914.49022.25431.07812.40463.15503.63245.61176.21005.27252.8899

picture of benzocyclobutadiene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C3 121.692 C1 C2 H10 118.547
C1 C7 C6 149.404 C1 C7 N8 122.222
C2 C1 C7 116.085 C2 C1 H9 120.133
C2 C3 C4 121.692 C2 C3 H11 119.760
C3 C2 H10 119.760 C3 C4 N8 116.085
C3 C4 H12 120.133 C4 C3 H11 118.547
C4 N8 C5 149.404 C4 N8 C7 122.222
C5 C6 C7 91.626 C5 C6 H14 135.333
C5 N8 C7 88.374 C6 C5 N8 91.626
C6 C5 H13 135.333 C6 C7 N8 88.374
C7 C1 H9 123.781 C7 C6 H14 133.041
N8 C4 H12 123.781 N8 C5 H13 133.041
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBE1PBE/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.300      
2 C -0.217      
3 C -0.217      
4 C -0.300      
5 C -0.163      
6 C -0.163      
7 C 0.015      
8 C 0.015      
9 H 0.222      
10 H 0.222      
11 H 0.222      
12 H 0.222      
13 H 0.221      
14 H 0.221      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 0.522 0.522
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -51.977 0.000 0.000
y 0.000 -39.954 0.000
z 0.000 0.000 -38.697
Traceless
 xyz
x -12.651 0.000 0.000
y 0.000 5.383 0.000
z 0.000 0.000 7.268
Polar
3z2-r214.536
x2-y2-12.023
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.012 0.000 0.000
y 0.000 12.287 0.000
z 0.000 0.000 14.709


<r2> (average value of r2) Å2
<r2> 221.909
(<r2>)1/2 14.897