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)	0.00	0.00	kJ mol-1	CODATA
Hfg(0K)	0.00	0.00	kJ mol-1	CODATA
Entropy (298.15K)	202.79	0.00	J K-1 mol-1	CODATA
Integrated Heat Capacity (0 to 298.15K)	8.82	0.00	kJ mol-1	CODATA
Heat Capacity (298.15K)	31.30		J K-1 mol-1	Gurvich

Information can also be found for this species in the NIST Chemistry Webbook

Vibrational levels (cm^-1)

Mode Number	Symmetry	Frequency (cm-1)	Frequency Reference	Intensity (km mol-1)	Int. unc.	Intensity Reference	Comment
1	Σg	917	2007Iri:389

Detailed diatomic data

ωe	ωexe	ωeye	Be	αe	ZPE	reference
916.929	11.3221	-0.10572	0.889294	0.0125952	455.4118	2007Iri:389

vibrational zero-point energy: 458.5 cm^-1
Calculated vibrational frequencies for F₂^- (flourine diatomic anion).

Rotational Constants (cm^-1)
See section I.F.4 to change rotational constant units

A	B	C	reference	comment
	0.88929		2007Iri:389

Calculated rotational constants for F₂^- (flourine diatomic anion).

Product of moments of inertia
18.9562	amu Å2		3.1478E-39	gm cm2

Geometric Data

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
rFF	1.412		1	2			1979HUB/HER

Cartesians

Atom	x (Å)	y (Å)	z (Å)
F1	0.0000	0.0000	0.0000
F2	0.0000	0.0000	1.4119

Atom - Atom Distances
Distances in Å

	F1	F2
F1		1.4119
F2	1.4119

Calculated geometries for F₂^- (flourine diatomic anion).

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond

Bond Type	Count
F-F	1

Connectivity

Atom 1	Atom 2
F1	F2

Electronic energy levels (cm^-1)

Energy (cm-1)	Degeneracy	reference	description
0	1	1979HUB/HER	1Σg

Ionization Energies (eV)

Ionization Energy	I.E. unc.	vertical I.E.	v.I.E. unc.	Electron Affinity	E.A. unc.	reference
15.697	0.003	15.700		3.005	0.071	webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment
For a molecule with D_∞h symmetry there is no dipole.
Electric quadrupole moment
Calculated electric quadrupole moments for F₂^- (flourine diatomic anion).

References
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squib	reference	DOI
1979HUB/HER	Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979
2007Iri:389	KK Irikura "Experimental Vibrational Zero-Point Energies: Diatomic Molecules" J. Phys. Chem. Ref. Data 36(2), 389, 2007	10.1063/1.2436891
CODATA	Cox, J.D.; Wagman, D.D.; Medvedev, V.A.CODATA Key Values for Thermodynamics. Hemisphere, New York, 1989
Gurvich	Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989	10.1351/pac198961061027
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)

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