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All results from a given calculation for C5H4O2 (4-Cyclopentene-1,3-dione)

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-340.143016
Energy at 298.15K-340.147712
Nuclear repulsion energy262.755876
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 3273 3114 1.38      
2 A1 3122 2970 0.24      
3 A1 1686 1604 4.57      
4 A1 1592 1514 1.98      
5 A1 1517 1443 16.13      
6 A1 1201 1143 74.00      
7 A1 1097 1044 71.10      
8 A1 813 774 3.61      
9 A1 567 539 4.53      
10 A1 368 350 8.97      
11 A2 1216 1157 0.00      
12 A2 1014 964 0.00      
13 A2 671 638 0.00      
14 A2 277 264 0.00      
15 B1 3172 3018 0.15      
16 B1 997 949 28.32      
17 B1 823 783 36.71      
18 B1 468 445 3.22      
19 B1 99 94 11.73      
20 B2 3248 3090 0.15      
21 B2 1650 1569 124.37      
22 B2 1374 1307 13.42      
23 B2 1291 1228 7.83      
24 B2 1086 1033 0.03      
25 B2 789 751 3.36      
26 B2 692 658 0.48      
27 B2 510 485 1.69      

Unscaled Zero Point Vibrational Energy (zpe) 17306.0 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 16463.2 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
0.21896 0.07019 0.05369

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 0.000 1.098
C2 0.000 1.221 0.150
C3 0.000 -1.221 0.150
C4 0.000 0.675 -1.260
C5 0.000 -0.675 -1.260
O6 0.000 2.426 0.470
O7 0.000 -2.426 0.470
H8 0.890 0.000 1.737
H9 -0.890 0.000 1.737
H10 0.000 1.324 -2.127
H11 0.000 -1.324 -2.127

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 O6 O7 H8 H9 H10 H11
C11.54611.54612.45342.45342.50632.50631.09521.09523.48673.4867
C21.54612.44201.51192.36321.24703.66132.19122.19122.27953.4148
C31.54612.44202.36321.51193.66131.24702.19122.19123.41482.2795
C42.45341.51192.36321.35102.46153.55173.19863.19861.08262.1791
C52.45342.36321.51191.35103.55172.46153.19863.19862.17911.0826
O62.50631.24703.66132.46153.55174.85252.87812.87812.82174.5615
O72.50633.66131.24703.55172.46154.85252.87812.87814.56152.8217
H81.09522.19122.19123.19863.19862.87812.87811.77974.18054.1805
H91.09522.19122.19123.19863.19862.87812.87811.77974.18054.1805
H103.48672.27953.41481.08262.17912.82174.56154.18054.18052.6473
H113.48673.41482.27952.17911.08264.56152.82174.18054.18052.6473

picture of 4-Cyclopentene-1,3-dione state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 106.691 C1 C2 O6 127.281
C1 C3 C5 106.691 C1 C3 O7 127.281
C2 C1 C3 104.316 C2 C1 H8 110.958
C2 C1 H9 110.958 C2 C4 C5 111.151
C2 C4 H10 122.071 C3 C1 H8 110.958
C3 C1 H9 110.958 C3 C5 C4 111.151
C3 C5 H11 122.071 C4 C2 O6 126.028
C4 C5 H11 126.778 C5 C3 O7 126.028
C5 C4 H10 126.778 H8 C1 H9 108.673
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability