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Experimental data for C2Br4 (tetrabromoethene)

22 02 02 11 45
Other names
Ethylene, tetrabromo-; Tetrabromoethylene; Ethene, tetrabromo-;
State Conformation
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
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 Ag 1535   webbook       C=C str
2 Ag 265           CBr2 s-str
3 Ag 144           CBr2 sciss
4 Au 66           CBr2 twist
5 B1u 635           B3U CBr2 s-str
6 B1u 188           B3U CBr2 sciss
7 B2g 464           CBr2 wag
8 B2u 766           CBr2 a-str
9 B2u 119           CBr2 rock
10 B3g 880           B1G CBr2 a-str
11 B3g 208           B1G CBr2 rock
12 B3u 245           B1U CBr2 wag

vibrational zero-point energy: 2757.5 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for C2Br4 (tetrabromoethene).
Gas-phase IR spectra can be found in the NIST Chemistry Webbook here.
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment

Calculated rotational constants for C2Br4 (tetrabromoethene).
Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of tetrabromoethene

Point Group D2h

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

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å

Calculated geometries for C2Br4 (tetrabromoethene).

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C=C 1
C-Br 4

Atom 1 Atom 2
C1 C2
C1 Br3
C1 Br4
C2 Br5
C2 Br6
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
9.105       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 1AG D2h True           D2h 0 2
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 C2Br4 (tetrabromoethene).
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 1AG D2h True       D2h 0 2

Calculated electric quadrupole moments for C2Br4 (tetrabromoethene).

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squib reference DOI
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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