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All results from a given calculation for C4H2O3 (Maleic Anhydride)

using model chemistry: MP2/6-31G(2df,p)

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at MP2/6-31G(2df,p)
 hartrees
Energy at 0K-378.488501
Energy at 298.15K-378.491789
HF Energy-377.263606
Nuclear repulsion energy275.085473
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 MP2/6-31G(2df,p)
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 3319 3135 1.95      
2 A1 1909 1803 42.93      
3 A1 1638 1547 4.46      
4 A1 1291 1219 137.53      
5 A1 1078 1019 20.19      
6 A1 885 836 5.45      
7 A1 634 599 0.16      
8 A1 404 382 9.92      
9 A2 973 919 0.00      
10 A2 782 739 0.00      
11 A2 262 247 0.00      
12 B1 865 817 62.89      
13 B1 647 611 0.12      
14 B1 164 155 2.42      
15 B2 3297 3114 2.53      
16 B2 1852 1749 435.54      
17 B2 1333 1259 0.43      
18 B2 1074 1014 98.61      
19 B2 926 874 131.55      
20 B2 705 665 30.78      
21 B2 561 530 4.44      

Unscaled Zero Point Vibrational Energy (zpe) 12298.4 cm-1
Scaled (by 0.9445) Zero Point Vibrational Energy (zpe) 11615.9 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 MP2/6-31G(2df,p)
ABC
0.22895 0.08222 0.06049

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31G(2df,p)

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.970
C2 0.000 1.126 0.158
C3 0.000 -1.126 0.158
O4 0.000 2.238 0.599
O5 0.000 -2.238 0.599
C6 0.000 0.668 -1.257
C7 0.000 -0.668 -1.257
H8 0.000 1.362 -2.084
H9 0.000 -1.362 -2.084

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.38771.38772.26802.26802.32482.32483.34363.3436
C21.38772.25161.19603.39211.48742.28522.25473.3491
C31.38772.25163.39211.19602.28521.48743.34912.2547
O42.26801.19603.39214.47502.43063.44822.82244.4895
O52.26803.39211.19604.47503.44822.43064.48952.8224
C62.32481.48742.28522.43063.44821.33691.07922.1923
C72.32482.28521.48743.44822.43061.33692.19231.0792
H83.34362.25473.34912.82244.48951.07922.19232.7239
H93.34363.34912.25474.48952.82242.19231.07922.7239

picture of Maleic Anhydride state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 O4 122.587 O1 C2 C6 107.872
O1 C3 O5 122.587 O1 C3 C7 107.872
C2 O1 C3 108.440 C2 C6 C7 107.908
C2 C6 H8 122.107 C3 C7 C6 107.908
C3 C7 H9 122.107 O4 C2 C6 129.541
O5 C3 C7 129.541 C6 C7 H9 129.985
C7 C6 H8 129.985
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability