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All results from a given calculation for H2CO3 (Carbonic acid)

using model chemistry: PBEPBE/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 PBEPBE/3-21G
 hartrees
Energy at 0K-263.245511
Energy at 298.15K-263.249061
HF Energy-263.245511
Nuclear repulsion energy119.789958
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 PBEPBE/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 3415 3384 0.26      
2 A1 1735 1719 265.25      
3 A1 1254 1242 35.79      
4 A1 898 890 9.60      
5 A1 501 497 6.92      
6 A2 473 469 0.00      
7 B1 723 716 50.32      
8 B1 589 583 261.75      
9 B2 3410 3379 58.13      
10 B2 1457 1444 55.11      
11 B2 1026 1017 453.24      
12 B2 556 551 51.20      

Unscaled Zero Point Vibrational Energy (zpe) 8018.1 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 7945.1 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 PBEPBE/3-21G
ABC
0.37182 0.36142 0.18327

See section I.F.4 to change rotational constant units
Geometric Data calculated at PBEPBE/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.116
O2 0.000 0.000 1.351
O3 0.000 1.108 -0.707
O4 0.000 -1.108 -0.707
H5 0.000 1.908 -0.098
H6 0.000 -1.908 -0.098

Atom - Atom Distances (Å)
  C1 O2 O3 O4 H5 H6
C11.23521.38011.38011.91991.9199
O21.23522.33702.33702.39572.3957
O31.38012.33702.21691.00493.0773
O41.38012.33702.21693.07731.0049
H51.91992.39571.00493.07733.8161
H61.91992.39573.07731.00493.8161

picture of Carbonic acid state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 O3 H5 106.149 C1 O4 H6 106.149
O2 C1 O3 126.568 O2 C1 O4 126.568
O3 C1 O4 106.863
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.731      
2 O -0.466      
3 O -0.505      
4 O -0.505      
5 H 0.372      
6 H 0.372      


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 0.320 0.320
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -21.603 0.000 0.000
y 0.000 -13.211 0.000
z 0.000 0.000 -28.596
Traceless
 xyz
x -0.700 0.000 0.000
y 0.000 11.889 0.000
z 0.000 0.000 -11.189
Polar
3z2-r2-22.378
x2-y2-8.393
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 0.967 0.000 0.000
y 0.000 3.751 0.000
z 0.000 0.000 2.977


<r2> (average value of r2) Å2
<r2> 62.828
(<r2>)1/2 7.926