return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

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

using model chemistry: B3LYP/CEP-121G

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/CEP-121G
 hartrees
Energy at 0K-71.594551
Energy at 298.15K 
HF Energy-71.594551
Nuclear repulsion energy136.929499
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/CEP-121G
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 3257 3174 0.03      
2 A1 1773 1728 44.70      
3 A1 1607 1566 2.18      
4 A1 1203 1172 95.06      
5 A1 1069 1042 55.62      
6 A1 832 811 12.87      
7 A1 604 589 1.78      
8 A1 374 364 10.76      
9 A2 960 936 0.00      
10 A2 713 695 0.00      
11 A2 255 248 0.00      
12 B1 851 830 86.96      
13 B1 607 592 1.04      
14 B1 161 157 2.39      
15 B2 3231 3148 0.65      
16 B2 1708 1665 549.98      
17 B2 1321 1288 1.85      
18 B2 1037 1011 40.34      
19 B2 825 804 120.74      
20 B2 686 668 56.90      
21 B2 527 514 7.40      

Unscaled Zero Point Vibrational Energy (zpe) 11800.9 cm-1
Scaled (by 0.9745) Zero Point Vibrational Energy (zpe) 11500.0 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/CEP-121G
See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/CEP-121G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 1.004
C2 0.000 1.165 0.153
C3 0.000 -1.165 0.153
O4 0.000 2.312 0.601
O5 0.000 -2.312 0.601
C6 0.000 0.678 -1.273
C7 0.000 -0.678 -1.273
H8 0.000 1.365 -2.108
H9 0.000 -1.365 -2.108

Atom - Atom Distances (Å)
  O1 C2 C3 O4 O5 C6 C7 H8 H9
O11.44291.44292.34692.34692.37582.37583.39873.3987
C21.44292.33061.23113.50601.50712.33042.27043.3939
C31.44292.33063.50601.23112.33041.50713.39392.2704
O42.34691.23113.50604.62402.48653.52862.87014.5677
O52.34693.50601.23114.62403.52862.48654.56772.8701
C62.37581.50712.33042.48653.52861.35561.08192.2073
C72.37582.33041.50713.52862.48651.35562.20731.0819
H83.39872.27043.39392.87014.56771.08192.20732.7306
H93.39873.39392.27044.56772.87012.20731.08192.7306

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 122.524 O1 C2 C6 107.267
O1 C3 O5 122.524 O1 C3 C7 107.267
C2 O1 C3 107.724 C2 C6 C7 108.872
C2 C6 H8 121.677 C3 C7 C6 108.872
C3 C7 H9 121.677 O4 C2 C6 130.210
O5 C3 C7 130.210 C6 C7 H9 129.451
C7 C6 H8 129.451
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/CEP-121G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.143      
2 C -0.027      
3 C -0.027      
4 O -0.042      
5 O -0.042      
6 C -0.096      
7 C -0.096      
8 H 0.237      
9 H 0.237      


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 -5.055 5.055
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -37.983 0.000 0.000
y 0.000 -50.151 0.000
z 0.000 0.000 -37.390
Traceless
 xyz
x 5.788 0.000 0.000
y 0.000 -12.464 0.000
z 0.000 0.000 6.677
Polar
3z2-r213.354
x2-y212.168
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.504 0.000 0.000
y 0.000 12.108 0.000
z 0.000 0.000 6.536


<r2> (average value of r2) Å2
<r2> 140.970
(<r2>)1/2 11.873