National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Listing of experimental data for FO2 (Dioxygen monofluoride)

Other names
Oxygen fluoride;
State Conformation
2A" 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 25.40 2.00 kJ mol-1 JANAF
Hfg(0K) enthalpy of formation 27.20 2.00 kJ mol-1 JANAF
Entropy (298.15K) entropy 259.50 0.20 J K-1 mol-1 JANAF
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 11.26   kJ mol-1 JANAF
Heat Capacity (298.15K) heat capacity 44.45   J K-1 mol-1 JANAF
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 A' 1487 webbook      
2 A' 579 webbook      
3 A' 376 1973Bon/Nib:2125      

vibrational zero-point energy: 1221.1 cm-1
Calculated vibrational frequencies for FO2 (Dioxygen monofluoride).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
2.61900 0.33401 0.29537 1984Yam/Hir:4694

Calculated rotational constants for FO2 (Dioxygen monofluoride).

Product of moments of inertia moments of inertia
18541.21amu3Å6   8.48997036155156E-116gm3 cm6
Geometric Data
picture of Dioxygen monofluoride

Point Group Cs

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 1.200   1 2 1984Yam/Hir:4694
rFO 1.649   2 3 1984Yam/Hir:4694
aOOF 111.19 1 2 3 1984Yam/Hir:4694


Atom x (Å) y (Å) z (Å)
O1 1.1475 0.2276 0.0000
O2 0.0000 0.5789 0.0000
F3 -1.0200 -0.7169 0.0000

Atom - Atom Distances bond lengths
Distances in Å

  O1 O2 F3
O1   1.20002.3643
O2 1.2000   1.6490
F3 2.36431.6490  

Calculated geometries for FO2 (Dioxygen monofluoride).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle
O1 O2 F3 111.190

Bond descriptions

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


Atom 1 Atom 2
O1 O2
O2 F3
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 2   2A"

Ionization Energies (eV)

Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
12.600 0.200     webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Calculated electric dipole moments for FO2 (Dioxygen monofluoride).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for FO2 (Dioxygen monofluoride).

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squib reference DOI
1973Bon/Nib:2125 VE Bondybey, JW Nibler "Infrared and Raman spectra of solid and matrix isolated diimide, HNNH" J. Chem. Phys. 58, 2125, 1973 10.1063/1.1679478
1984Yam/Hir:4694 Yamada, C.; Hirota, E. "The Infrared diode laser spectrum of the (nu)2 band of the FO2 radical." Journal of Chemical Physics. 80, 4694-4700 (1984) 10.1063/1.446534
JANAF Chase, M.W., Jr.; Davies, C.A.; Downey, J.R., Jr.; Frurip, D.J.; McDonald, R.A.; Syverud, A.N., JANAF Thermochemical Tables (Third Edition), J. Phys. Chem. Ref. Data,Suppl. 1, 1985, 14, 1.  
webbook NIST Chemistry Webbook (  

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