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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: HF/CEP-121G*

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-121G*
 hartrees
Energy at 0K-25.386958
Energy at 298.15K-25.393399
Nuclear repulsion energy60.970639
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-121G*
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 3370 3044 29.85      
2 A1 3203 2893 75.95      
3 A1 1752 1583 3.17      
4 A1 1633 1475 0.20      
5 A1 1357 1226 0.12      
6 A1 1210 1093 0.26      
7 A1 1063 960 0.40      
8 A1 959 866 2.11      
9 A2 3233 2921 0.00      
10 A2 1282 1158 0.00      
11 A2 1135 1026 0.00      
12 A2 1036 936 0.00      
13 A2 339 307 0.00      
14 B1 3251 2937 114.05      
15 B1 1197 1081 12.10      
16 B1 937 847 28.40      
17 B1 714 645 57.72      
18 B2 3337 3015 25.52      
19 B2 3191 2883 82.68      
20 B2 1606 1451 0.49      
21 B2 1446 1307 14.92      
22 B2 1352 1222 2.50      
23 B2 959 867 14.86      
24 B2 929 839 0.70      

Unscaled Zero Point Vibrational Energy (zpe) 20244.6 cm-1
Scaled (by 0.9034) Zero Point Vibrational Energy (zpe) 18289.0 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-121G*
ABC
0.43440 0.40673 0.22796

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/CEP-121G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.666 0.838
C2 0.000 -0.666 0.838
C3 0.000 0.785 -0.683
C4 0.000 -0.785 -0.683
H5 0.000 1.406 1.622
H6 0.000 -1.406 1.622
H7 0.884 1.244 -1.120
H8 -0.884 -1.244 -1.120
H9 -0.884 1.244 -1.120
H10 0.884 -1.244 -1.120

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.33101.52572.10211.07842.21492.22482.87412.22482.8741
C21.33102.10211.52572.21491.07842.87412.22482.87412.2248
C31.52572.10211.57092.38703.18051.08752.25611.08752.2561
C42.10211.52571.57093.18052.38702.25611.08752.25611.0875
H51.07842.21492.38703.18052.81212.88553.91422.88553.9142
H62.21491.07843.18052.38702.81213.91422.88553.91422.8855
H72.22482.87411.08752.25612.88553.91423.05181.76832.4874
H82.87412.22482.25611.08753.91422.88553.05182.48741.7683
H92.22482.87411.08752.25612.88553.91421.76832.48743.0518
H102.87412.22482.25611.08753.91422.88552.48741.76833.0518

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 94.508 C1 C2 H6 133.369
C1 C3 C4 85.492 C1 C3 H7 115.701
C1 C3 H9 115.701 C2 C1 C3 94.508
C2 C1 H5 133.369 C2 C4 C3 85.492
C2 C4 H8 115.701 C2 C4 H10 115.701
C3 C1 H5 132.124 C3 C4 H8 114.922
C3 C4 H10 114.922 C4 C2 H6 132.124
C4 C3 H7 114.922 C4 C3 H9 114.922
H7 C3 H9 108.782 H8 C4 H10 108.782
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-121G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.187      
2 C -0.187      
3 C -0.349      
4 C -0.349      
5 H 0.219      
6 H 0.219      
7 H 0.158      
8 H 0.158      
9 H 0.158      
10 H 0.158      


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 -0.147 0.147
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -26.400 0.000 0.000
y 0.000 -24.035 0.000
z 0.000 0.000 -24.737
Traceless
 xyz
x -2.013 0.000 0.000
y 0.000 1.533 0.000
z 0.000 0.000 0.480
Polar
3z2-r20.961
x2-y2-2.364
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 4.630 0.000 0.000
y 0.000 7.516 0.000
z 0.000 0.000 6.254


<r2> (average value of r2) Å2
<r2> 57.025
(<r2>)1/2 7.552