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

using model chemistry: HF/CEP-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 HF/CEP-31G*
 hartrees
Energy at 0K-70.204502
Energy at 298.15K-70.208072
HF Energy-70.204502
Nuclear repulsion energy141.059971
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 HF/CEP-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 3477 3122 0.10      
2 A1 2133 1915 116.97      
3 A1 1821 1635 0.37      
4 A1 1433 1287 240.45      
5 A1 1159 1041 12.50      
6 A1 955 857 7.73      
7 A1 689 619 0.66      
8 A1 440 395 20.29      
9 A2 1066 957 0.00      
10 A2 838 753 0.00      
11 A2 277 249 0.00      
12 B1 958 861 100.20      
13 B1 705 633 2.84      
14 B1 173 155 4.75      
15 B2 3451 3099 0.18      
16 B2 2053 1843 1118.14      
17 B2 1446 1298 0.42      
18 B2 1216 1092 143.06      
19 B2 1054 947 81.59      
20 B2 764 686 19.32      
21 B2 601 540 1.65      

Unscaled Zero Point Vibrational Energy (zpe) 13353.8 cm-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 11991.7 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 HF/CEP-31G*
ABC
0.22639 0.08349 0.06100

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/CEP-31G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.954
C2 0.000 1.119 0.169
C3 0.000 -1.119 0.169
O4 0.000 2.218 0.610
O5 0.000 -2.218 0.610
C6 0.000 0.669 -1.270
C7 0.000 -0.669 -1.270
H8 0.000 1.365 -2.090
H9 0.000 -1.365 -2.090

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.36721.36722.24422.24422.32212.32213.33593.3359
C21.36722.23851.18393.36611.50712.29512.27213.3575
C31.36722.23853.36611.18392.29511.50713.35752.2721
O42.24421.18393.36614.43552.43553.44512.83174.4863
O52.24423.36611.18394.43553.44512.43554.48632.8317
C62.32211.50712.29512.43553.44511.33861.07562.1934
C72.32212.29511.50713.44512.43551.33862.19341.0756
H83.33592.27213.35752.83174.48631.07562.19342.7298
H93.33593.35752.27214.48632.83172.19341.07562.7298

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 123.056 O1 C2 C6 107.679
O1 C3 O5 123.056 O1 C3 C7 107.679
C2 O1 C3 109.899 C2 C6 C7 107.372
C2 C6 H8 122.333 C3 C7 C6 107.372
C3 C7 H9 122.333 O4 C2 C6 129.266
O5 C3 C7 129.266 C6 C7 H9 130.295
C7 C6 H8 130.295
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.147      
2 C 0.024      
3 C 0.024      
4 O -0.137      
5 O -0.137      
6 C -0.132      
7 C -0.132      
8 H 0.319      
9 H 0.319      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 -4.730 4.730
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -37.464 0.000 0.000
y 0.000 -49.918 0.000
z 0.000 0.000 -36.423
Traceless
 xyz
x 5.707 0.000 0.000
y 0.000 -12.975 0.000
z 0.000 0.000 7.268
Polar
3z2-r214.536
x2-y212.454
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.411 0.000 0.000
y 0.000 10.452 0.000
z 0.000 0.000 5.769


<r2> (average value of r2) Å2
<r2> 133.916
(<r2>)1/2 11.572