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II.A.1. (XV.A.)

Listing of experimental data for O3 (Ozone)

Other names
Ozon; Ozone; Triatomic oxygen; trioxidane;
InChI=1/O3/c1-3-2 O=[O+][O-] trioxidane
State Conformation
1A1 CS
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Hfg(298.15K) enthalpy of formation 141.80 2.00 kJ mol-1 Gurvich see JCP 111(14), 6350, 1999
Hfg(0K) enthalpy of formation 144.45 2.00 kJ mol-1 Gurvich see JCP 111(14), 6350, 1999
Entropy (298.15K) entropy 239.01   J K-1 mol-1 Gurvich see JCP 111(14), 6350, 1999
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 10.37   kJ mol-1 Gurvich see JCP 111(14), 6350, 1999
Heat Capacity (298.15K) heat capacity 39.37   J K-1 mol-1 Gurvich see JCP 111(14), 6350, 1999
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
1 A1 1110 1966Herzberg 1.0 0.2 1985Adl/Lan:255
2 A1 705 1966Herzberg 3.9 0.4 1985Adl/Lan:255
3 B2 1042 VEEL5 84.1 4.3 1985Adl/Lan:255

vibrational zero-point energy: 1428.5 cm-1
Calculated vibrational frequencies for O3 (Ozone).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
3.55348 0.44525 0.39479 1966Herzberg

Calculated rotational constants for O3 (Ozone).

Product of moments of inertia moments of inertia
7669.475amu3Å6   3.51183117268652E-116gm3 cm6

Geometric Data
picture of Ozone

Point Group C2v

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees
Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rOO 1.278   1 2 1966Herzberg
aOOO 116.8 2 1 3 1966Herzberg

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 0.0000
O2 0.0000 1.0885 0.6697
O3 0.0000 -1.0885 0.6697

Atom - Atom Distances bond lengths
Distances in Å
  O1 O2 O3
O1   1.27801.2780
O2 1.2780   2.1770
O3 1.27802.1770  

Calculated geometries for O3 (Ozone).

Experimental Bond Angles (degrees) from cartesians bond angles
atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
O2 O1 O3 116.800

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
O=O 2

Atom 1 Atom 2
O1 O2
O1 O3

Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A1
10000 1 1966Herzberg

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
12.530 0.080 12.730   webbook

Electron Affinity (eV)
Electron Affinity unc. reference
2.103 0.003 2002Rie/Tsc:231

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
0.530 NSRDS-NBS10  

Calculated electric dipole moments for O3 (Ozone).
Electric quadrupole moment quadrupole
Quadrupole (D Å) Reference comment
xx yy zz
9.200 -17.100 7.900 1974Hel/Hel(II/6) aa=-17.1+-5.2 bb=9.2+-E28 cc=7.9+-7.9

Calculated electric quadrupole moments for O3 (Ozone).

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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1974Hel/Hel(II/6) Hellwege, KH and AM Hellwege (eds.). Landolt-Bornstein: Group II: Volume 6 Molecular Constants from Microwave, Molecular Beam, and Electron Spin Resonance Spectroscopy Springer-Verlag. Berlin. 1974.  
1985Adl/Lan:255 SM Adler-Golden, SR Langhoff, CW Bauschlicher Jr., GD Carney "Theoretical calculation of ozone vibrational infrared intensities" J. Chem. Phys. 83(1), 255, 1985 10.1063/1.449818
2002Rie/Tsc:231 JC Rienstra-Kiracofe, GS Tschumper, HF Schaefer III, S Nandi, GB Ellison "Atomic and Molecular Electron Affinities: Photoelectron Experiments and Theoretical Computations" Chemical Reviews 2002, 102, 231-282 10.1021/cr990044u
Gurvich Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989 10.1351/pac198961061027
NSRDS-NBS10 R. D. Nelson Jr., D. R. Lide, A. A. Maryott "Selected Values of electric dipole moments for molecules in the gas phase" NSRDS-NBS10, 1967  
VEEL5 M.E. Jacox, Vibrational and Electronic Energy Levels of Polyatomic Transient Molecules, J. Phys. Chem.Ref. Data, Monograph 3 (1994) (updated data in NIST Chemistry Webbook -  
webbook NIST Chemistry Webbook (  

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