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

using model chemistry: B3LYP/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at B3LYP/3-21G*
 hartrees
Energy at 0K-377.185383
Energy at 298.15K 
HF Energy-377.185383
Nuclear repulsion energy271.177388
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 B3LYP/3-21G*
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 3304 3179 0.70      
2 A1 1883 1811 35.53      
3 A1 1655 1592 3.20      
4 A1 1204 1158 72.94      
5 A1 1087 1046 82.45      
6 A1 830 798 3.87      
7 A1 630 606 0.24      
8 A1 386 371 7.71      
9 A2 1036 997 0.00      
10 A2 781 751 0.00      
11 A2 296 285 0.00      
12 B1 895 861 93.18      
13 B1 650 625 0.18      
14 B1 175 168 0.85      
15 B2 3281 3156 1.15      
16 B2 1809 1740 381.86      
17 B2 1350 1299 9.23      
18 B2 1008 970 29.72      
19 B2 851 818 97.83      
20 B2 700 673 45.46      
21 B2 542 522 4.77      

Unscaled Zero Point Vibrational Energy (zpe) 12175.3 cm-1
Scaled (by 0.962) Zero Point Vibrational Energy (zpe) 11712.7 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 B3LYP/3-21G*
See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.991
C2 0.000 1.157 0.154
C3 0.000 -1.157 0.154
O4 0.000 2.282 0.598
O5 0.000 -2.282 0.598
C6 0.000 0.667 -1.262
C7 0.000 -0.667 -1.262
H8 0.000 1.346 -2.099
H9 0.000 -1.346 -2.099

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.42761.42762.31602.31602.34992.34993.37013.3701
C21.42762.31311.21023.46751.49852.30902.26073.3672
C31.42762.31313.46751.21022.30901.49853.36722.2607
O42.31601.21023.46754.56482.46373.48712.85464.5208
O52.31603.46751.21024.56483.48712.46374.52082.8546
C62.34991.49852.30902.46373.48711.33421.07732.1800
C72.34992.30901.49853.48712.46371.33422.18001.0773
H83.37012.26073.36722.85464.52081.07732.18002.6921
H93.37013.36722.26074.52082.85462.18001.07732.6921

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 122.590 O1 C2 C6 106.826
O1 C3 O5 122.590 O1 C3 C7 106.826
C2 O1 C3 108.220 C2 C6 C7 109.064
C2 C6 H8 121.871 C3 C7 C6 109.064
C3 C7 H9 121.871 O4 C2 C6 130.584
O5 C3 C7 130.584 C6 C7 H9 129.066
C7 C6 H8 129.066
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.501      
2 C 0.656      
3 C 0.656      
4 O -0.428      
5 O -0.428      
6 C -0.222      
7 C -0.222      
8 H 0.245      
9 H 0.245      


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 -4.210 4.210
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -37.451 0.000 0.000
y 0.000 -46.607 0.000
z 0.000 0.000 -36.383
Traceless
 xyz
x 4.044 0.000 0.000
y 0.000 -9.690 0.000
z 0.000 0.000 5.646
Polar
3z2-r211.292
x2-y29.156
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.157 0.000 0.000
y 0.000 10.141 0.000
z 0.000 0.000 5.463


<r2> (average value of r2) Å2
<r2> 175.229
(<r2>)1/2 13.237