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

using model chemistry: CISD/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 CISD/3-21G*
 hartrees
Energy at 0K-340.043076
Energy at 298.15K-340.047991
Nuclear repulsion energy265.636960
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 CISD/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 3350 3130 0.61      
2 A1 3181 2972 0.28      
3 A1 1879 1756 11.94      
4 A1 1714 1602 1.40      
5 A1 1540 1439 19.37      
6 A1 1254 1172 92.73      
7 A1 1142 1067 58.82      
8 A1 847 791 2.82      
9 A1 596 557 5.81      
10 A1 388 363 15.20      
11 A2 1261 1178 0.00      
12 A2 1093 1022 0.00      
13 A2 703 657 0.00      
14 A2 293 274 0.00      
15 B1 3227 3015 0.00      
16 B1 1044 975 41.43      
17 B1 862 806 37.00      
18 B1 483 452 1.34      
19 B1 106 99 15.43      
20 B2 3324 3106 0.00      
21 B2 1836 1716 286.08      
22 B2 1422 1329 14.42      
23 B2 1345 1257 3.34      
24 B2 1149 1073 1.87      
25 B2 831 776 1.67      
26 B2 721 674 0.98      
27 B2 532 497 1.00      

Unscaled Zero Point Vibrational Energy (zpe) 18061.2 cm-1
Scaled (by 0.9344) Zero Point Vibrational Energy (zpe) 16876.4 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 CISD/3-21G*
ABC
0.22158 0.07209 0.05495

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 1.093
C2 0.000 1.210 0.151
C3 0.000 -1.210 0.151
C4 0.000 0.667 -1.253
C5 0.000 -0.667 -1.253
O6 0.000 2.392 0.464
O7 0.000 -2.392 0.464
H8 0.885 0.000 1.729
H9 -0.885 0.000 1.729
H10 0.000 1.315 -2.112
H11 0.000 -1.315 -2.112

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 O6 O7 H8 H9 H10 H11
C11.53391.53392.43952.43952.47292.47291.08981.08983.46493.4649
C21.53392.42081.50602.34421.22203.61552.17692.17692.26603.3911
C31.53392.42082.34421.50603.61551.22202.17692.17693.39112.2660
C42.43951.50602.34421.33332.43423.50753.18163.18161.07622.1596
C52.43952.34421.50601.33333.50752.43423.18163.18162.15961.0762
O62.47291.22203.61552.43423.50754.78312.84662.84662.79274.5140
O72.47293.61551.22203.50752.43424.78312.84662.84664.51402.7927
H81.08982.17692.17693.18163.18162.84662.84661.77034.15574.1557
H91.08982.17692.17693.18163.18162.84662.84661.77034.15574.1557
H103.46492.26603.39111.07622.15962.79274.51404.15574.15572.6294
H113.46493.39112.26602.15961.07624.51402.79274.15574.15572.6294

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 106.734 C1 C2 O6 127.251
C1 C3 C5 106.734 C1 C3 O7 127.251
C2 C1 C3 104.201 C2 C1 H8 111.001
C2 C1 H9 111.001 C2 C4 C5 111.165
C2 C4 H10 121.807 C3 C1 H8 111.001
C3 C1 H9 111.001 C3 C5 C4 111.165
C3 C5 H11 121.807 C4 C2 O6 126.015
C4 C5 H11 127.027 C5 C3 O7 126.015
C5 C4 H10 127.027 H8 C1 H9 108.618
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability