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 PBr3 (Phosphorus tribromide)

Other names
Tribromophosphane; Tribromophosphine;
InChI=1S/Br3P/c1-4(2)3 IPNPIHIZVLFAFP-UHFFFAOYSA-N BrP(Br)Br Tribromophosphane
State Conformation
1A1 C3V
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 -146.02   kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy 348.22   J K-1 mol-1 webbook
Heat Capacity (298.15K) heat capacity 75.94   J K-1 mol-1 webbook
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

Calculated vibrational frequencies for PBr3 (Phosphorus tribromide).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.03450   1971Kuc/Shi:2584

Calculated rotational constants for PBr3 (Phosphorus tribromide).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of Phosphorus tribromide

Point Group C3v

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
rPBr 2.220 0.003 1 2 1976Hellwege(II/7)
aBrPBr 101 0.4 2 1 3 1976Hellwege(II/7)


Atom x (Å) y (Å) z (Å)
P1 0.0000 0.0000 0.8819
Br2 0.0000 1.9780 -0.1260
Br3 1.7130 -0.9890 -0.1260
Br4 -1.7130 -0.9890 -0.1260

Atom - Atom Distances bond lengths
Distances in Å

  P1 Br2 Br3 Br4
P1   2.22002.22002.2200
Br2 2.2200   3.42613.4261
Br3 2.22003.4261   3.4261
Br4 2.22003.42613.4261  

Calculated geometries for PBr3 (Phosphorus tribromide).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
Br2 P1 Br3 101.002 Br2 P1 Br4 101.002
Br3 P1 Br4 101.002

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
P-Br 3


Atom 1 Atom 2
P1 Br2
P1 Br3
P1 Br4
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A1

Ionization Energies (eV)

Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
10.100 0.100     webbook

Electron Affinity (eV)

Electron Affinity unc. reference
1.590 0.150 webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
0.610 1954Kis:86  

Calculated electric dipole moments for PBr3 (Phosphorus tribromide).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for PBr3 (Phosphorus tribromide).

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squib reference DOI
1954Kis:86 P Kisluk "Dipole Moments, Nuclear Quadrupole Coupling, and the Bonding Orbitals in Group V - Trihalides" Journal of Chemical Physics 22(1) p86 1954 10.1063/1.1739863
1971Kuc/Shi:2584 K Kuchitsu, T Shibata, A Yokozeki, C Matsumura "Molecular Structure of Phosphorus Tribromide as Studied by Gas Electron Diffraction and Microwave Spectroscopy" Inorganic Chemistry 10(11) p 2584 1971 10.1021/ic50105a042
1976Hellwege(II/7) Hellwege, KH and AM Hellwege (ed.). Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 7: Structure Data of Free Polyatomic Molecules. Springer-Verlag. Berlin. 1976.  
webbook NIST Chemistry Webbook (  

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