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)	191.61		J K-1 mol-1	CODATA
Integrated Heat Capacity (0 to 298.15K)	8.67		kJ mol-1	CODATA
Heat Capacity (298.15K)	29.12		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	2359	Shim

Detailed diatomic data

ωe	ωexe	ωeye	Be	αe	ZPE	reference
2358.57	14.324	-0.00226	1.998241	0.017318	1175.778	2007Iri:389

vibrational zero-point energy: 1179.3 cm^-1
Calculated vibrational frequencies for N₂^- (nitrogen diatomic anion).

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

A	B	C	reference	comment
	1.99824		1979HUB/HER

Calculated rotational constants for N₂^- (nitrogen diatomic anion).

Product of moments of inertia
8.436234	amu Å2		1.400892E-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
rNN	1.098		1	2			1979HUB/HER

Cartesians

Atom	x (Å)	y (Å)	z (Å)
N1	0.0000	0.0000	0.5488
N2	0.0000	0.0000	-0.5488

Atom - Atom Distances
Distances in Å

	N1	N2
N1		1.0977
N2	1.0977

Calculated geometries for N₂^- (nitrogen diatomic anion).

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

Bond Type	Count
N#N	1

Connectivity

Atom 1	Atom 2
N1	N2

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
15.581	0.008	15.581				webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment
For a molecule with D_∞h symmetry there is no dipole.
Electric quadrupole moment

Quadrupole (D Å)			Reference	comment
xx	yy	zz
0.697	0.697	-1.394	1998Gra/Imr:49	-4.65+-0.08 E-40 Cm^2

Calculated electric quadrupole moments for N₂^- (nitrogen diatomic anion).
Electric dipole polarizability (ų)

alpha	unc.	Reference
1.710		1997Oln/Can:59

Calculated electric dipole polarizability for N₂^- (nitrogen 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
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
1998Gra/Imr:49	C Graham, DA Imrie, RE Raab "Measurement of the electric quadrupole moments of CO2, CO, N2, Cl2 and BF3" Mol. Phys. 93(1), 1998, 49-56	10.1080/002689798169429
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
Shim	Shimanouchi, T. , Tables of Molecular Vibrational Frequencies, Consolidated Volume 1, NSRDS NBS-39
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)

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