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Experimental data for BrCN (Cyanogen bromide)

22 02 02 11 45
Other names
Bromine cyanide; Bromocyan; Bromocyanide; Bromocyanogen; Cyanobromide; Cyanogen monobromide; Bromine monocyanide; Cyanic bromide;
State Conformation
1Σ C*V
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 186.19 6.30 kJ mol-1 JANAF
Hfg(0K) enthalpy of formation 192.75 6.30 kJ mol-1 JANAF
Entropy (298.15K) entropy 248.36 0.04 J K-1 mol-1 JANAF
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 11.07   kJ mol-1  
Heat Capacity (298.15K) heat capacity 47.12   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 Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference
1 Σ 2198   1997Esp/Tam:495-497       nu 3 in reference CN stretch
2 Σ 576   1997Esp/Tam:495-497       nu 1 in reference CBr stretch
3 Π 342   1997Esp/Tam:495-497       bend

vibrational zero-point energy: 1728.8 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for BrCN (Cyanogen bromide).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.13717 0.13717 JANAF B0

Calculated rotational constants for BrCN (Cyanogen bromide).
Product of moments of inertia moments of inertia
122.8941amu Å2   2.040736E-38gm cm2
Geometric Data
picture of Cyanogen bromide

Point Group C∞v

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
rCN 1.158   1 2 JANAF
rCBr 1.789   1 3 JANAF

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.0000
N2 0.0000 0.0000 1.1580
Br3 0.0000 0.0000 -1.7890

Atom - Atom Distances bond lengths
Distances in Å
  C1 N2 Br3
C1   1.15801.7890
N2 1.1580   2.9470
Br3 1.78902.9470  

Calculated geometries for BrCN (Cyanogen bromide).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle
N2 C1 Br3 180.000

Bond descriptions

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

Atom 1 Atom 2
C1 N2
C1 Br3
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1Σ

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
12.000 1.000     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 1Σ C∞v True           C∞v 1 1
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 BrCN (Cyanogen bromide).
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 1Σ C∞v True       C∞v 1 1

Calculated electric quadrupole moments for BrCN (Cyanogen bromide).
Electric dipole polarizability (Å3) polarizability
alpha unc. Reference
5.824   1997Oln/Can:59

Calculated electric dipole polarizability for BrCN (Cyanogen bromide).

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squib reference DOI
1997Esp/Tam:495-497 CD Esposti,F Tamassia, C Puzzarini, R Tarroni, Z Zelinger "Millimetre-wave and infrared spectroscopy of Br13CN: anharmonic force field of cyanogen bromide from spectroscopic data and ab initio calculations" Molecular Physics, Volume 90, 1997, 495-497 10.1080/002689797172624
1997Oln/Can:59 TN Olney, NM Cann, G Cooper, CE Brion, Absolute scale determination for photoabsorption spectra and the calculation of molecular properties using dipole sum-rules, Chem. Phys. 223 (1997) 59-98 10.1016/S0301-0104(97)00145-6
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 ( 10.18434/T4D303

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