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

Listing of experimental data for BO2 (Boron dioxide)

Other names
Boron oxide;
InChI=1/BO2/c2-1-3 O=B=O
State Conformation
2A' D*H
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 -309.13 20.00 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation -310.00 20.00 kJ mol-1 Gurvich
Entropy (298.15K) entropy 230.13   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 10.77   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 43.28   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 (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
1 Σu 1278 VEEL5      
2 Σg 1056 VEEL5      
3 Πu 448 VEEL5      

vibrational zero-point energy: 1615.5 cm-1
Calculated vibrational frequencies for BO2 (Boron dioxide).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.32920   1966Herzberg

Calculated rotational constants for BO2 (Boron dioxide).

Product of moments of inertia moments of inertia
51.20787amu Å2   8.5034E-39gm cm2

Geometric Data
picture of Boron dioxide

Point Group D∞h

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
rBO 1.265   1 2 1966Herzberg
aOBO 180 2 1 3 1966Herzberg

Atom x (Å) y (Å) z (Å)
B1 0.0000 0.0000 0.0000
O2 0.0000 0.0000 1.2650
O3 0.0000 0.0000 -1.2650

Atom - Atom Distances bond lengths
Distances in Å
  B1 O2 O3
B1   1.26501.2650
O2 1.2650   2.5300
O3 1.26502.5300  

Calculated geometries for BO2 (Boron dioxide).

Experimental Bond Angles (degrees) from cartesians bond angles
atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
O2 B1 O3 180.000

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

Atom 1 Atom 2
B1 O2
B1 O3

Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 2 1966Herzberg 2A'
150.1 2 Gurvich
18291.5 4 1966Herzberg

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
14.000 1.000     webbook

Electron Affinity (eV)
Electron Affinity unc. reference
4.320 0.190 webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
For a molecule with D∞h symmetry there is no dipole.
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for BO2 (Boron dioxide).

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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
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
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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