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All results from a given calculation for C5H8 (Cyclopentene)

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 CS 1A'
Energy calculated at MP2=FULL/3-21G*
 hartrees
Energy at 0K-193.356415
Energy at 298.15K-193.365389
Nuclear repulsion energy169.413173
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 A' 3244 3076 18.42      
2 A' 3168 3004 34.57      
3 A' 3131 2968 25.62      
4 A' 3109 2948 16.52      
5 A' 3082 2921 11.99      
6 A' 1649 1563 0.20      
7 A' 1595 1513 1.46      
8 A' 1576 1494 1.15      
9 A' 1357 1287 2.07      
10 A' 1292 1225 1.56      
11 A' 1186 1124 0.07      
12 A' 1109 1051 4.79      
13 A' 961 911 1.32      
14 A' 891 844 0.50      
15 A' 840 796 0.16      
16 A' 734 696 35.13      
17 A' 634 601 17.18      
18 A' 136 129 0.12      
19 A" 3214 3047 5.05      
20 A" 3131 2968 10.30      
21 A" 3082 2922 40.39      
22 A" 1587 1504 1.28      
23 A" 1415 1342 1.38      
24 A" 1383 1311 0.25      
25 A" 1364 1293 4.04      
26 A" 1257 1192 0.04      
27 A" 1219 1155 0.92      
28 A" 1037 983 0.29      
29 A" 975 924 0.01      
30 A" 935 887 1.03      
31 A" 889 842 4.89      
32 A" 796 754 0.31      
33 A" 392 372 0.04      

Unscaled Zero Point Vibrational Energy (zpe) 26184.6 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 24823.0 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 MP2=FULL/3-21G*
ABC
0.23790 0.23595 0.12838

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.268 -1.222 0.000
C2 -0.070 -0.332 1.253
C3 -0.070 -0.332 -1.253
C4 -0.070 1.088 0.673
C5 -0.070 1.088 -0.673
H6 1.339 -1.446 0.000
H7 -0.288 -2.164 0.000
H8 -1.058 -0.580 1.661
H9 -1.058 -0.580 -1.661
H10 -0.105 1.973 1.300
H11 -0.105 1.973 -1.300
H12 0.671 -0.458 -2.050
H13 0.671 -0.458 2.050

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 H6 H7 H8 H9 H10 H11 H12 H13
C11.57311.57312.42932.42931.09481.09372.22002.22003.46863.46862.22432.2243
C21.57312.50501.53362.39222.18992.22981.09803.08682.30523.43873.38681.0954
C31.57312.50502.39221.53362.18992.22983.08681.09803.43872.30521.09543.3868
C42.42931.53362.39221.34552.97663.32762.17653.03441.08482.16193.21762.1991
C52.42932.39221.53361.34552.97663.32763.03442.17652.16191.08482.19913.2176
H61.09482.18992.18992.97662.97661.77873.04243.04243.93233.93232.37182.3718
H71.09372.22982.22983.32763.32761.77872.42042.42044.33944.33942.83372.8337
H82.22001.09803.08682.17653.03443.04242.42043.32252.74904.02404.09591.7759
H92.22003.08681.09803.03442.17653.04242.42043.32254.02402.74901.77594.0959
H103.46862.30523.43871.08482.16193.93234.33942.74904.02402.59924.21082.6597
H113.46863.43872.30522.16191.08483.93234.33944.02402.74902.59922.65974.2108
H122.22433.38681.09543.21762.19912.37182.83374.09591.77594.21082.65974.1000
H132.22431.09543.38682.19913.21762.37182.83371.77594.09592.65974.21084.1000

picture of Cyclopentene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 102.871 C1 C2 H8 111.182
C1 C2 H13 111.679 C1 C3 C5 102.871
C1 C3 H9 111.182 C1 C3 H12 111.679
C2 C1 C3 105.541 C2 C1 H6 109.019
C2 C1 H7 112.218 C2 C4 C5 112.212
C2 C4 H10 122.448 C3 C1 H6 109.019
C3 C1 H7 112.218 C3 C5 C4 112.212
C3 C5 H11 122.448 C4 C2 H8 110.504
C4 C2 H13 112.471 C4 C5 H11 125.300
C5 C3 H9 110.504 C5 C3 H12 112.471
C5 C4 H10 125.300 H6 C1 H7 108.725
H8 C2 H13 108.123 H9 C3 H12 108.123
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability