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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: HF/CEP-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at HF/CEP-31G*
 hartrees
Energy at 0K-25.373487
Energy at 298.15K-25.379885
Nuclear repulsion energy60.688399
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 HF/CEP-31G*
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 3404 3057 28.69      
2 A1 3239 2909 81.41      
3 A1 1784 1602 4.64      
4 A1 1632 1466 0.24      
5 A1 1359 1221 0.04      
6 A1 1217 1093 0.19      
7 A1 1066 957 0.31      
8 A1 969 870 2.22      
9 A2 3272 2939 0.00      
10 A2 1283 1152 0.00      
11 A2 1103 991 0.00      
12 A2 1028 923 0.00      
13 A2 317 285 0.00      
14 B1 3292 2956 134.31      
15 B1 1196 1074 12.47      
16 B1 939 843 29.23      
17 B1 711 638 61.29      
18 B2 3366 3022 23.28      
19 B2 3228 2899 86.32      
20 B2 1602 1438 0.39      
21 B2 1446 1298 13.28      
22 B2 1343 1206 2.09      
23 B2 966 867 18.51      
24 B2 923 829 0.26      

Unscaled Zero Point Vibrational Energy (zpe) 20341.8 cm-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 18267.0 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 HF/CEP-31G*
ABC
0.42940 0.40373 0.22581

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/CEP-31G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.674 0.841
C2 0.000 -0.674 0.841
C3 0.000 0.787 -0.686
C4 0.000 -0.787 -0.686
H5 0.000 1.418 1.626
H6 0.000 -1.418 1.626
H7 0.888 1.245 -1.124
H8 -0.888 -1.245 -1.124
H9 -0.888 1.245 -1.124
H10 0.888 -1.245 -1.124

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.34861.53112.11351.08122.23472.23072.88702.23072.8870
C21.34862.11351.53112.23471.08122.88702.23072.88702.2307
C31.53112.11351.57402.39633.19471.09112.26061.09112.2606
C42.11351.53111.57403.19472.39632.26061.09112.26061.0911
H51.08122.23472.39633.19472.83612.89493.92982.89493.9298
H62.23471.08123.19472.39632.83613.92982.89493.92982.8949
H72.23072.88701.09112.26062.89493.92983.05881.77602.4904
H82.88702.23072.26061.09113.92982.89493.05882.49041.7760
H92.23072.88701.09112.26062.89493.92981.77602.49043.0588
H102.88702.23072.26061.09113.92982.89492.49041.77603.0588

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 94.221 C1 C2 H6 133.461
C1 C3 C4 85.779 C1 C3 H7 115.557
C1 C3 H9 115.557 C2 C1 C3 94.221
C2 C1 H5 133.461 C2 C4 C3 85.779
C2 C4 H8 115.557 C2 C4 H10 115.557
C3 C1 H5 132.318 C3 C4 H8 114.834
C3 C4 H10 114.834 C4 C2 H6 132.318
C4 C3 H7 114.834 C4 C3 H9 114.834
H7 C3 H9 108.946 H8 C4 H10 108.946
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.275      
2 C -0.275      
3 C -0.217      
4 C -0.217      
5 H 0.267      
6 H 0.267      
7 H 0.112      
8 H 0.112      
9 H 0.112      
10 H 0.112      


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 -0.178 0.178
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -26.205 0.000 0.000
y 0.000 -23.904 0.000
z 0.000 0.000 -24.619
Traceless
 xyz
x -1.944 0.000 0.000
y 0.000 1.509 0.000
z 0.000 0.000 0.435
Polar
3z2-r20.871
x2-y2-2.302
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.947 0.000 0.000
y 0.000 7.280 0.000
z 0.000 0.000 5.913


<r2> (average value of r2) Å2
<r2> 57.291
(<r2>)1/2 7.569