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Experimental data for Na2F2 (Sodium Fluoride Dimer)

22 02 02 11 45
Other names
Disodium difluoride; Sodium, di-​μ-​fluorodi-;
InChI=1S/2F.2Na [Na]1F[Na]F1
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
Hfg(298.15K) enthalpy of formation -846.42   kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy 287.33   J K-1 mol-1 webbook
Heat Capacity (298.15K) heat capacity 70.63   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 Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference

Calculated vibrational frequencies for Na2F2 (Sodium Fluoride Dimer).
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 Na2F2 (Sodium Fluoride Dimer).
Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of Sodium Fluoride Dimer

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
rFNa 2.081 0.010 1 3 1988Har/Fin:6058-6063
aFNaF 84.6 0.6 3 1 4 1988Har/Fin:6058-6063
aNaFNa 95.4 0.6 1 3 2 1988Har/Fin:6058-6063 by symmetry

Atom x (Å) y (Å) z (Å)
Na1 0.0000 0.0000 1.4010
Na2 0.0000 0.0000 -1.4010
F3 0.0000 1.5390 0.0000
F4 0.0000 -1.5390 0.0000

Atom - Atom Distances bond lengths
Distances in Å
  Na1 Na2 F3 F4
Na1   2.80202.08122.0812
Na2 2.8020   2.08122.0812
F3 2.08122.0812   3.0780
F4 2.08122.08123.0780  

Calculated geometries for Na2F2 (Sodium Fluoride Dimer).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
Na1 F3 Na2 84.625 Na1 F4 Na2 84.625
F3 Na1 F4 95.375 F3 Na2 F4 95.375

Bond descriptions

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

Atom 1 Atom 2
Na1 F3
Na1 F4
Na2 F3
Na2 F4
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
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 Na2F2 (Sodium Fluoride Dimer).
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 Na2F2 (Sodium Fluoride Dimer).

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squib reference DOI
1988Har/Fin:6058-6063 JG Hartley, and M Fink "An electron diffraction study of alkali fluoride vapors" J. Chem. Phys. 89, 6058 (1988) 10.1063/1.455420
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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