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

Listing of experimental data for KF (Potassium Fluoride)

InChI=1/K.F [K]F
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 -326.77   kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy 226.60   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
1 Σ 428 webbook      

vibrational zero-point energy: 214.0 cm-1
Calculated vibrational frequencies for KF (Potassium Fluoride).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  0.27994 0.27994 webbook

Calculated rotational constants for KF (Potassium Fluoride).

Product of moments of inertia moments of inertia
60.21928amu Å2   9.999803E-39gm cm2

Geometric Data
picture of Potassium Fluoride

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
rKF 2.171 0.000 1 2 NISTdiatomic re 39K 19F

Atom x (Å) y (Å) z (Å)
K1 0.0000 0.0000 0.0000
F2 0.0000 0.0000 2.1715

Atom - Atom Distances bond lengths
Distances in Å
  K1 F2
K1   2.1715
F2 2.1715  

Calculated geometries for KF (Potassium Fluoride).

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
F-K 1

Atom 1 Atom 2
K1 F2

Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1Σ
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
8.558 NISTdiatomic mu e

Calculated electric dipole moments for KF (Potassium Fluoride).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for KF (Potassium Fluoride).

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