National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
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.3. (XII.A.1.)

Listing of experimental geometry data for HO2 (Hydroperoxy radical)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
20.35652 1.11803 1.05632
Rotational Constants from 1982Cha/Del:426
Calculated rotational constants for HO2 (Hydroperoxy radical).

Point Group C∞v

Internal coordinates

(distances (r) in Å) (angles (a) in degrees) (dihedrals (d) in degrees)
Description Value Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rOH 0.971 1 3 1984Lub/Ama:4826 re values
rOO 1.331 1 2 1984Lub/Ama:4826 re value
aHOO 104.29 2 1 3 1984Lub/Ama:4826 equilibrium value
picture of Hydroperoxy radical

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
O1 0.0553 -0.6132 0.0000
O2 0.0553 0.7198 0.0000
H3 -0.8853 -0.8528 0.0000

Atom - Atom Distances (Å)

  O1 O2 H3

Calculated geometries for HO2 (Hydroperoxy radical).
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squib reference DOI
1982Cha/Del:426 Charo, A.; De Lucia, F. "The Millimeter and Submillimter Spectrum of HO2: The Effects of Unpaired Electronic Spin in a Light Asymmetric Rotor." Journal of Molecular Spectroscopy. 94, 426-436 (1982) 10.1016/0022-2852(82)90018-2
1984Lub/Ama:4826 KG Lubic, T Amano, H Uehara, K Kawaguchi, E Hirota :The nu1 band of the DO2 radical by difference frequency laser and diode laser spectroscopy: The equilibrium sturcture of the hydroperoxyl radical" J. Chem. Phys. 81, 4826, 1984 10.1063/1.447508

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