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Experimental data for KrF2 (Krypton difluoride)

22 02 02 11 45
State Conformation
1Σg 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
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 Σg 449   webbook       KrF2 s-stretch
2 Σu 593   webbook       KrF2 a-stretch
3 Πu 235   webbook       bend

vibrational zero-point energy: 755.8 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for KrF2 (Krypton difluoride).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.12626   1968Mur/Rei:5690-5693

Calculated rotational constants for KrF2 (Krypton difluoride).
Product of moments of inertia moments of inertia
133.5152amu Å2   2.217107E-38gm cm2
Geometric Data
picture of Krypton difluoride

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
rFKr 1.875 0.002 1 2 1968Mur/Rei:5690-5693
aFKrF 180 2 1 3 1968Mur/Rei:5690-5693 by symmetry

Atom x (Å) y (Å) z (Å)
Kr1 0.0000 0.0000 0.0000
F2 0.0000 0.0000 1.8750
F3 0.0000 0.0000 -1.8750

Atom - Atom Distances bond lengths
Distances in Å
  Kr1 F2 F3
Kr1   1.87501.8750
F2 1.8750   3.7500
F3 1.87503.7500  

Calculated geometries for KrF2 (Krypton difluoride).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle
F2 Kr1 F3 180.000

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
F-Kr 2

Atom 1 Atom 2
Kr1 F2
Kr1 F3
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1Σg

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
13.060   13.340   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 1Σg D∞h True           D∞h 0 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 KrF2 (Krypton difluoride).
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 1Σg D∞h True       D∞h 0 1

Calculated electric quadrupole moments for KrF2 (Krypton difluoride).

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squib reference DOI
1968Mur/Rei:5690-5693 C Murchison, S Reichman, D Anderson, J Overend, F Schreiner "The Structure of Krypton Difluoride" J. Am. Chem. Soc. 90(21), 1968, 5690-5693 10.1021/ja01023a007
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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