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Experimental data for FO (Oxygen monofluoride)

22 02 02 11 45
Other names
Oxygen fluoride;
State Conformation
2Π C*V
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 109.00 10.00 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation 108.38 10.00 kJ mol-1 Gurvich
Entropy (298.15K) entropy 216.28   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 9.37   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 31.87   J K-1 mol-1 Gurvich
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference
1 Σ 1033 1053 2007Iri:389      

Detailed diatomic data
ωe ωexe ωeye Be αe ZPE reference
1053.014 9.919395 -6.095684E-02 1.058708 1.329513E-02 524.0532 2007Iri:389

vibrational zero-point energy: 516.5 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for FO (Oxygen monofluoride).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  1.05871   2007Iri:389

Calculated rotational constants for FO (Oxygen monofluoride).
Product of moments of inertia moments of inertia
15.92283amu Å2   2.64409E-39gm cm2
Geometric Data
picture of Oxygen monofluoride

Point Group C∞v

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
rFO 1.354   1 2 2000Tam/Bro:5523 re

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 0.0000
F2 0.0000 0.0000 1.3541

Atom - Atom Distances bond lengths
Distances in Å
  O1 F2
O1   1.3541
F2 1.3541  

Calculated geometries for FO (Oxygen monofluoride).

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
O-F 1

Atom 1 Atom 2
O1 F2
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 2 1979HUB/HER 2Π
196.108 2 1999Tam/Bro

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
12.770       webbook

Electron Affinity (eV)
Electron Affinity unc. reference
2.272 0.006 webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
State Config State description Conf description Exp. min. Dipole (Debye) Reference comment Point Group Components
x y z total dipole quadrupole
1 1 2Π C∞v True       0.004 1992LBII/19c 0.0004 C∞v 1 1
Experimental dipole measurement abbreviations: MW microwave; DT Dielectric with Temperature variation; DR Indirect (usually an upper limit); MB Molecular beam
Calculated electric dipole moments for FO (Oxygen monofluoride).
Electric quadrupole moment quadrupole
State Config State description Conf description Exp. min. Quadrupole (D Å) Reference comment Point Group Components
xx yy zz dipole quadrupole
1 1 2Π C∞v True       C∞v 1 1

Calculated electric quadrupole moments for FO (Oxygen monofluoride).

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squib reference DOI
1979HUB/HER Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules, Van Nostrand Reinhold Co., 1979 10.1007/978-1-4757-0961-2
1992LBII/19c Landolt-Bornstein Numerical Data and Functional Relationships in Science and Technology, New Series, II/19c (1992) Spreinger-Verlag, Heidelberg  
1999Tam/Bro Filippo Tammassia, John M. Brown, Kenneth Evenson, J. Chem. Phys. 110, 7273, 1999 10.1063/1.478630
2000Tam/Bro:5523 Tamassia, F.; Brown, J.; Saita, S. "The detection of the free radical FO (X2 PI 3/2) by submillimeter-wave spectroscopy." Journal of Chemical Physics. 112, 5523-5526 (2000) 10.1063/1.481184
2007Iri:389 KK Irikura "Experimental Vibrational Zero-Point Energies: Diatomic Molecules" J. Phys. Chem. Ref. Data 36(2), 389, 2007 10.1063/1.2436891
Gurvich Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989  
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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