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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: MP2/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at MP2/3-21G*
 hartrees
Energy at 0K-154.386984
Energy at 298.15K-154.393190
HF Energy-154.028472
Nuclear repulsion energy111.392505
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 MP2/3-21G*
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 3270 3110 17.00      
2 A1 3124 2972 23.86      
3 A1 1593 1515 0.01      
4 A1 1552 1477 0.52      
5 A1 1242 1181 2.87      
6 A1 1148 1092 0.01      
7 A1 975 928 0.00      
8 A1 828 788 1.22      
9 A2 3173 3018 0.00      
10 A2 1205 1146 0.00      
11 A2 1057 1006 0.00      
12 A2 918 874 0.00      
13 A2 301 287 0.00      
14 B1 3188 3033 36.74      
15 B1 1147 1091 4.13      
16 B1 904 860 15.23      
17 B1 675 643 57.18      
18 B2 3232 3075 10.59      
19 B2 3117 2965 24.82      
20 B2 1561 1485 0.26      
21 B2 1338 1273 7.98      
22 B2 1274 1212 11.48      
23 B2 885 842 3.78      
24 B2 844 803 3.72      

Unscaled Zero Point Vibrational Energy (zpe) 19275.2 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 18336.5 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 MP2/3-21G*
ABC
0.41781 0.39429 0.22009

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.679 0.831
C2 0.000 -0.679 0.831
C3 0.000 0.807 -0.717
C4 0.000 -0.807 -0.717
H5 0.000 1.422 1.617
H6 0.000 -1.422 1.617
H7 0.898 1.252 -1.152
H8 -0.898 -1.252 -1.152
H9 -0.898 1.252 -1.152
H10 0.898 -1.252 -1.152

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.35791.55322.14591.08202.24352.25142.91002.25142.9100
C21.35792.14591.55322.24351.08202.91002.25142.91002.2514
C31.55322.14591.61442.41383.22781.09282.28811.09282.2881
C42.14591.55321.61443.22782.41382.28811.09282.28811.0928
H51.08202.24352.41383.22782.84472.91663.95312.91663.9531
H62.24351.08203.22782.41382.84473.95312.91663.95312.9166
H72.25142.91001.09282.28812.91663.95313.08131.79692.5032
H82.91002.25142.28811.09283.95312.91663.08132.50321.7969
H92.25142.91001.09282.28812.91663.95311.79692.50323.0813
H102.91002.25142.28811.09283.95312.91662.50321.79693.0813

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 94.737 C1 C2 H6 133.400
C1 C3 C4 85.263 C1 C3 H7 115.510
C1 C3 H9 115.510 C2 C1 C3 94.737
C2 C1 H5 133.400 C2 C4 C3 85.263
C2 C4 H8 115.510 C2 C4 H10 115.510
C3 C1 H5 131.863 C3 C4 H8 113.993
C3 C4 H10 113.993 C4 C2 H6 131.863
C4 C3 H7 113.993 C4 C3 H9 113.993
H7 C3 H9 110.597 H8 C4 H10 110.597
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability