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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: MP2/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 MP2/CEP-31G*
 hartrees
Energy at 0K-25.852022
Energy at 298.15K-25.858179
HF Energy-25.371435
Nuclear repulsion energy60.074434
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 MP2/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 3235 3072 22.65      
2 A1 3104 2947 47.27      
3 A1 1605 1524 1.55      
4 A1 1525 1448 0.19      
5 A1 1241 1178 1.66      
6 A1 1146 1088 0.20      
7 A1 1013 962 0.09      
8 A1 924 877 2.59      
9 A2 3169 3008 0.00      
10 A2 1183 1123 0.00      
11 A2 1014 963 0.00      
12 A2 912 866 0.00      
13 A2 272 259 0.00      
14 B1 3182 3021 68.29      
15 B1 1111 1055 8.68      
16 B1 884 839 19.76      
17 B1 654 620 77.43      
18 B2 3195 3034 14.14      
19 B2 3099 2942 43.97      
20 B2 1499 1423 0.50      
21 B2 1325 1258 12.00      
22 B2 1219 1157 3.41      
23 B2 920 874 18.24      
24 B2 841 798 0.12      

Unscaled Zero Point Vibrational Energy (zpe) 19134.9 cm-1
Scaled (by 0.9494) Zero Point Vibrational Energy (zpe) 18166.6 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 MP2/CEP-31G*
ABC
0.41883 0.39859 0.22185

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-31G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.689 0.824
C2 0.000 -0.689 0.824
C3 0.000 0.792 -0.709
C4 0.000 -0.792 -0.709
H5 0.000 1.445 1.619
H6 0.000 -1.445 1.619
H7 0.902 1.250 -1.155
H8 -0.902 -1.250 -1.155
H9 -0.902 1.250 -1.155
H10 0.902 -1.250 -1.155

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.37821.53732.13251.09672.27742.24622.91372.24622.9137
C21.37822.13251.53732.27741.09672.91372.24622.91372.2462
C31.53732.13251.58472.41793.22911.10502.27631.10502.2763
C42.13251.53731.58473.22912.41792.27631.10502.27631.1050
H51.09672.27742.41793.22912.89062.92313.97102.92313.9710
H62.27741.09673.22912.41792.89063.97102.92313.97102.9231
H72.24622.91371.10502.27632.92313.97103.08221.80372.4993
H82.91372.24622.27631.10503.97102.92313.08222.49931.8037
H92.24622.91371.10502.27632.92313.97101.80372.49933.0822
H102.91372.24622.27631.10503.97102.92312.49931.80373.0822

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 93.851 C1 C2 H6 133.593
C1 C3 C4 86.149 C1 C3 H7 115.471
C1 C3 H9 115.471 C2 C1 C3 93.851
C2 C1 H5 133.593 C2 C4 C3 86.149
C2 C4 H8 115.471 C2 C4 H10 115.471
C3 C1 H5 132.557 C3 C4 H8 114.448
C3 C4 H10 114.448 C4 C2 H6 132.557
C4 C3 H7 114.448 C4 C3 H9 114.448
H7 C3 H9 109.410 H8 C4 H10 109.410
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability