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All results from a given calculation for C4H6 (Cyclobutene)

using model chemistry: MP2=FULL/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=FULL/3-21G
 hartrees
Energy at 0K-154.393577
Energy at 298.15K-154.399794
HF Energy-154.028517
Nuclear repulsion energy111.410608
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=FULL/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 3122 16.92      
2 A1 3124 2983 23.72      
3 A1 1593 1521 0.01      
4 A1 1553 1482 0.52      
5 A1 1242 1186 2.90      
6 A1 1148 1096 0.01      
7 A1 975 931 0.00      
8 A1 828 791 1.22      
9 A2 3173 3030 0.00      
10 A2 1205 1150 0.00      
11 A2 1057 1010 0.00      
12 A2 919 878 0.00      
13 A2 301 288 0.00      
14 B1 3189 3045 36.53      
15 B1 1147 1095 4.15      
16 B1 904 863 15.29      
17 B1 676 645 57.08      
18 B2 3233 3087 10.50      
19 B2 3117 2977 24.68      
20 B2 1561 1491 0.27      
21 B2 1339 1278 7.97      
22 B2 1274 1217 11.55      
23 B2 885 845 3.81      
24 B2 844 806 3.70      

Unscaled Zero Point Vibrational Energy (zpe) 19279.1 cm-1
Scaled (by 0.9548) Zero Point Vibrational Energy (zpe) 18407.7 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=FULL/3-21G
ABC
0.41795 0.39442 0.22016

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/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 1.251 -1.152
H8 -0.898 -1.251 -1.152
H9 -0.898 1.251 -1.152
H10 0.898 -1.251 -1.152

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6 H7 H8 H9 H10
C11.35761.55302.14551.08182.24312.25112.90952.25112.9095
C21.35762.14551.55302.24311.08182.90952.25112.90952.2511
C31.55302.14551.61422.41343.22731.09272.28781.09272.2878
C42.14551.55301.61423.22732.41342.28781.09272.28781.0927
H51.08182.24312.41343.22732.84422.91623.95262.91623.9526
H62.24311.08183.22732.41342.84423.95262.91623.95262.9162
H72.25112.90951.09272.28782.91623.95263.08091.79662.5028
H82.90952.25112.28781.09273.95262.91623.08092.50281.7966
H92.25112.90951.09272.28782.91623.95261.79662.50283.0809
H102.90952.25112.28781.09273.95262.91622.50281.79663.0809

picture of Cyclobutene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 94.738 C1 C2 H6 133.397
C1 C3 C4 85.262 C1 C3 H7 115.511
C1 C3 H9 115.511 C2 C1 C3 94.738
C2 C1 H5 133.397 C2 C4 C3 85.262
C2 C4 H8 115.511 C2 C4 H10 115.511
C3 C1 H5 131.865 C3 C4 H8 113.994
C3 C4 H10 113.994 C4 C2 H6 131.865
C4 C3 H7 113.994 C4 C3 H9 113.994
H7 C3 H9 110.594 H8 C4 H10 110.594
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability