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

using model chemistry: MP2=FULL/6-31G

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/6-31G
 hartrees
Energy at 0K-377.762983
Energy at 298.15K-377.765982
HF Energy-377.014989
Nuclear repulsion energy267.389767
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/6-31G
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 3291 3127 0.15      
2 A1 1756 1669 25.24      
3 A1 1606 1526 2.55      
4 A1 1201 1141 68.89      
5 A1 1082 1028 75.06      
6 A1 823 781 14.08      
7 A1 608 578 0.82      
8 A1 377 358 7.04      
9 A2 891 847 0.00      
10 A2 673 640 0.00      
11 A2 255 242 0.00      
12 B1 795 755 90.89      
13 B1 591 561 0.78      
14 B1 156 148 1.18      
15 B2 3268 3105 0.53      
16 B2 1696 1612 281.42      
17 B2 1354 1286 1.96      
18 B2 1036 984 54.46      
19 B2 795 755 133.91      
20 B2 683 649 110.81      
21 B2 537 510 22.47      

Unscaled Zero Point Vibrational Energy (zpe) 11736.7 cm-1
Scaled (by 0.9501) Zero Point Vibrational Energy (zpe) 11151.1 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/6-31G
ABC
0.22249 0.07648 0.05692

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/6-31G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 1.010
C2 0.000 1.172 0.150
C3 0.000 -1.172 0.150
O4 0.000 2.323 0.598
O5 0.000 -2.323 0.598
C6 0.000 0.678 -1.268
C7 0.000 -0.678 -1.268
H8 0.000 1.355 -2.117
H9 0.000 -1.355 -2.117

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.45351.45352.35952.35952.37682.37683.40703.4070
C21.45352.34481.23513.52441.50252.33202.27443.3949
C31.45352.34483.52441.23512.33201.50253.39492.2744
O42.35951.23513.52444.64682.48833.53482.88274.5715
O52.35953.52441.23514.64683.53482.48834.57152.8827
C62.37681.50252.33202.48833.53481.35641.08482.2026
C72.37682.33201.50253.53482.48831.35642.20261.0848
H83.40702.27443.39492.88274.57151.08482.20262.7091
H93.40703.39492.27444.57152.88272.20261.08482.7091

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 122.504 O1 C2 C6 107.028
O1 C3 O5 122.504 O1 C3 C7 107.028
C2 O1 C3 107.537 C2 C6 C7 109.204
C2 C6 H8 122.226 C3 C7 C6 109.204
C3 C7 H9 122.226 O4 C2 C6 130.469
O5 C3 C7 130.469 C6 C7 H9 128.570
C7 C6 H8 128.570
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability