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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: HF/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 HF/3-21G*
 hartrees
Energy at 0K-154.030718
Energy at 298.15K-154.037167
Nuclear repulsion energy112.856268
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/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 3427 3093 15.17      
2 A1 3245 2929 32.41      
3 A1 1761 1590 0.58      
4 A1 1642 1482 0.49      
5 A1 1338 1207 3.15      
6 A1 1211 1093 0.03      
7 A1 1025 925 0.22      
8 A1 891 804 2.49      
9 A2 3282 2962 0.00      
10 A2 1296 1170 0.00      
11 A2 1156 1043 0.00      
12 A2 1076 971 0.00      
13 A2 345 311 0.00      
14 B1 3299 2977 47.68      
15 B1 1226 1107 8.31      
16 B1 956 863 33.22      
17 B1 745 672 58.03      
18 B2 3388 3058 8.17      
19 B2 3235 2919 40.38      
20 B2 1622 1464 0.18      
21 B2 1424 1285 14.50      
22 B2 1379 1245 11.70      
23 B2 972 877 1.91      
24 B2 903 815 10.91      

Unscaled Zero Point Vibrational Energy (zpe) 20420.3 cm-1
Scaled (by 0.9026) Zero Point Vibrational Energy (zpe) 18431.3 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/3-21G*
ABC
0.43107 0.40229 0.22581

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.663 0.823
C2 0.000 -0.663 0.823
C3 0.000 0.797 -0.711
C4 0.000 -0.797 -0.711
H5 0.000 1.396 1.601
H6 0.000 -1.396 1.601
H7 0.888 1.242 -1.138
H8 -0.888 -1.242 -1.138
H9 -0.888 1.242 -1.138
H10 0.888 -1.242 -1.138

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.32621.53952.11741.06832.20072.22872.87412.22872.8741
C21.32622.11741.53952.20071.06832.87412.22872.87412.2287
C31.53952.11741.59342.38763.18561.08112.26401.08112.2640
C42.11741.53951.59343.18562.38762.26401.08112.26401.0811
H51.06832.20072.38763.18562.79132.88273.90412.88273.9041
H62.20071.06833.18562.38762.79133.90412.88273.90412.8827
H72.22872.87411.08112.26402.88273.90413.05291.77592.4833
H82.87412.22872.26401.08113.90412.88273.05292.48331.7759
H92.22872.87411.08112.26402.88273.90411.77592.48333.0529
H102.87412.22872.26401.08113.90412.88272.48331.77593.0529

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 94.979 C1 C2 H6 133.290
C1 C3 C4 85.021 C1 C3 H7 115.417
C1 C3 H9 115.417 C2 C1 C3 94.979
C2 C1 H5 133.290 C2 C4 C3 85.021
C2 C4 H8 115.417 C2 C4 H10 115.417
C3 C1 H5 131.731 C3 C4 H8 114.303
C3 C4 H10 114.303 C4 C2 H6 131.731
C4 C3 H7 114.303 C4 C3 H9 114.303
H7 C3 H9 110.440 H8 C4 H10 110.440
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.231 -0.188    
2 C -0.231 -0.188    
3 C -0.427 -0.010    
4 C -0.427 -0.010    
5 H 0.220 0.133    
6 H 0.220 0.133    
7 H 0.219 0.032    
8 H 0.219 0.032    
9 H 0.219 0.032    
10 H 0.219 0.032    


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 -0.076 0.076
CHELPG 0.000 0.000 -0.071 0.071
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -26.706 0.000 0.000
y 0.000 -24.330 0.000
z 0.000 0.000 -24.620
Traceless
 xyz
x -2.231 0.000 0.000
y 0.000 1.333 0.000
z 0.000 0.000 0.898
Polar
3z2-r21.796
x2-y2-2.376
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.579 0.000 0.000
y 0.000 6.734 0.000
z 0.000 0.000 5.472


<r2> (average value of r2) Å2
<r2> 66.349
(<r2>)1/2 8.146