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

using model chemistry: B3PW91/6-31G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at B3PW91/6-31G
 hartrees
Energy at 0K-379.004692
Energy at 298.15K-379.007941
HF Energy-379.004692
Nuclear repulsion energy271.547244
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 B3PW91/6-31G
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 3322 3181 0.72      
2 A1 1859 1780 42.36      
3 A1 1663 1593 4.06      
4 A1 1237 1185 103.33      
5 A1 1095 1049 47.66      
6 A1 868 831 12.05      
7 A1 631 605 0.93      
8 A1 391 374 10.24      
9 A2 1007 965 0.00      
10 A2 739 708 0.00      
11 A2 279 267 0.00      
12 B1 864 827 92.04      
13 B1 633 606 0.92      
14 B1 171 164 1.99      
15 B2 3299 3159 1.49      
16 B2 1791 1716 487.36      
17 B2 1357 1299 3.46      
18 B2 1063 1018 36.78      
19 B2 862 825 112.22      
20 B2 709 679 49.55      
21 B2 552 529 5.44      

Unscaled Zero Point Vibrational Energy (zpe) 12194.7 cm-1
Scaled (by 0.9577) Zero Point Vibrational Energy (zpe) 11678.8 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 B3PW91/6-31G
ABC
0.22800 0.07916 0.05876

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3PW91/6-31G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.986
C2 0.000 1.151 0.151
C3 0.000 -1.151 0.151
O4 0.000 2.283 0.596
O5 0.000 -2.283 0.596
C6 0.000 0.671 -1.255
C7 0.000 -0.671 -1.255
H8 0.000 1.351 -2.093
H9 0.000 -1.351 -2.093

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.42181.42182.31572.31572.33942.33943.36293.3629
C21.42182.30161.21623.46221.48582.30142.25353.3613
C31.42182.30163.46221.21622.30141.48583.36132.2535
O42.31571.21623.46224.56542.45453.48592.84634.5210
O52.31573.46221.21624.56543.48592.45454.52102.8463
C62.33941.48582.30142.45453.48591.34201.07962.1892
C72.33942.30141.48583.48592.45451.34202.18921.0796
H83.36292.25353.36132.84634.52101.07962.18922.7026
H93.36293.36132.25354.52102.84632.18921.07962.7026

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 122.574 O1 C2 C6 107.121
O1 C3 O5 122.574 O1 C3 C7 107.121
C2 O1 C3 108.077 C2 C6 C7 108.840
C2 C6 H8 122.098 C3 C7 C6 108.840
C3 C7 H9 122.098 O4 C2 C6 130.304
O5 C3 C7 130.304 C6 C7 H9 129.061
C7 C6 H8 129.061
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3PW91/6-31G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.484      
2 C 0.510      
3 C 0.510      
4 O -0.354      
5 O -0.354      
6 C -0.149      
7 C -0.149      
8 H 0.236      
9 H 0.236      


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 -4.773 4.773
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -37.351 0.000 0.000
y 0.000 -48.525 0.000
z 0.000 0.000 -36.618
Traceless
 xyz
x 5.221 0.000 0.000
y 0.000 -11.540 0.000
z 0.000 0.000 6.320
Polar
3z2-r212.639
x2-y211.174
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.606 0.000 0.000
y 0.000 11.100 0.000
z 0.000 0.000 5.873


<r2> (average value of r2) Å2
<r2> 175.227
(<r2>)1/2 13.237