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

using model chemistry: B1B95/6-311G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at B1B95/6-311G*
 hartrees
Energy at 0K-379.260253
Energy at 298.15K-379.263560
HF Energy-379.260253
Nuclear repulsion energy276.795409
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 B1B95/6-311G*
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 3290 3154 0.07      
2 A1 1957 1876 64.93      
3 A1 1690 1620 3.02      
4 A1 1300 1246 178.04      
5 A1 1082 1037 21.14      
6 A1 896 859 6.01      
7 A1 642 616 0.70      
8 A1 410 393 11.32      
9 A2 983 942 0.00      
10 A2 783 751 0.00      
11 A2 256 245 0.00      
12 B1 865 829 80.71      
13 B1 649 622 0.00      
14 B1 165 158 2.78      
15 B2 3269 3133 0.00      
16 B2 1896 1818 650.55      
17 B2 1342 1286 1.52      
18 B2 1076 1031 70.43      
19 B2 948 908 114.78      
20 B2 709 679 33.89      
21 B2 568 544 3.00      

Unscaled Zero Point Vibrational Energy (zpe) 12386.6 cm-1
Scaled (by 0.9586) Zero Point Vibrational Energy (zpe) 11873.8 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 B1B95/6-311G*
ABC
0.23133 0.08329 0.06124

See section I.F.4 to change rotational constant units
Geometric Data calculated at B1B95/6-311G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.962
C2 0.000 1.121 0.160
C3 0.000 -1.121 0.160
O4 0.000 2.223 0.597
O5 0.000 -2.223 0.597
C6 0.000 0.663 -1.250
C7 0.000 -0.663 -1.250
H8 0.000 1.355 -2.078
H9 0.000 -1.355 -2.078

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.37831.37832.25242.25242.31002.31003.32863.3286
C21.37832.24101.18553.37151.48262.27382.25013.3370
C31.37832.24103.37151.18552.27381.48263.33702.2501
O42.25241.18553.37154.44512.41743.42622.81194.4668
O52.25243.37151.18554.44513.42622.41744.46682.8119
C62.31001.48262.27382.41743.42621.32621.07872.1811
C72.31002.27381.48263.42622.41741.32622.18111.0787
H83.32862.25013.33702.81194.46681.07872.18112.7098
H93.32863.33702.25014.46682.81192.18111.07872.7098

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 122.763 O1 C2 C6 107.641
O1 C3 O5 122.763 O1 C3 C7 107.641
C2 O1 C3 108.777 C2 C6 C7 107.971
C2 C6 H8 122.136 C3 C7 C6 107.971
C3 C7 H9 122.136 O4 C2 C6 129.596
O5 C3 C7 129.596 C6 C7 H9 129.893
C7 C6 H8 129.893
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B1B95/6-311G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.266      
2 C 0.413      
3 C 0.413      
4 O -0.274      
5 O -0.274      
6 C -0.263      
7 C -0.263      
8 H 0.256      
9 H 0.256      


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 -4.105 4.105
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -37.085 0.000 0.000
y 0.000 -47.041 0.000
z 0.000 0.000 -35.783
Traceless
 xyz
x 4.326 0.000 0.000
y 0.000 -10.607 0.000
z 0.000 0.000 6.280
Polar
3z2-r212.561
x2-y29.955
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.309 0.000 0.000
y 0.000 10.546 0.000
z 0.000 0.000 6.206


<r2> (average value of r2) Å2
<r2> 168.824
(<r2>)1/2 12.993