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Experimental data for HNO3 (Nitric acid)

22 02 02 11 45
Other names
Acide nitrique; Acido nitrico; Aqua fortis; Azotic acid; Azotowy kwas; Hydrogen nitrate; Kyselina dusicne; NA 1760; Nitric Acid; Nitric acid fuming; Salpetersaure; Salpeterzuuroplossingen;
InChI=1S/HNO3/c2-1(3)4/h(H,2,3,4) GRYLNZFGIOXLOG-UHFFFAOYSA-N O=N(O)=O Nitric Acid
State Conformation
1A' CS
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 -133.91 0.60 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation -124.20 0.60 kJ mol-1 Gurvich
Entropy (298.15K) entropy 266.88   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 11.88   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 54.10   J K-1 mol-1 Gurvich
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 A' 3550   Shim       OH stretch
2 A' 1708   Shim       NO2 a-stretch
3 A' 1331   Shim       OH bend, NO stretch
4 A' 1325   Shim       OH bend, NO stretch
5 A' 879   Shim       NO stretch
6 A' 647   Shim       NO stretch
7 A' 579   Shim       NO2 rock
8 A" 762   Shim       NO2 wag
9 A" 456   1979HUB/HER       OH torsion

vibrational zero-point energy: 5618.5 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for HNO3 (Nitric acid).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
0.43401 0.40361 0.20883 1960Mil/Mor:1523

Calculated rotational constants for HNO3 (Nitric acid).
Product of moments of inertia moments of inertia
130959.7amu3Å6   5.99660634871594E-115gm3 cm6
Geometric Data
picture of Nitric acid

Point Group Cs

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
rOH 0.964   2 5 1965Cox/Riv:3106
rNO 1.406   1 2 1965Cox/Riv:3106 in NOH
rNO 1.211   1 3 1965Cox/Riv:3106
rNO 1.199   1 4 1965Cox/Riv:3106
aHON 102.15 1 2 5 1965Cox/Riv:3106
aONO 115.0883 2 1 3 1965Cox/Riv:3106
aONO 130.267 3 1 4 1965Cox/Riv:3106
aONO 113.85 2 1 4 1965Cox/Riv:3106

Atom x (Å) y (Å) z (Å)
N1 0.0000 0.1551 0.0000
O2 -0.2674 -1.2253 0.0000
O3 1.1744 0.4504 0.0000
O4 -0.9844 0.8396 0.0000
H5 0.6192 -1.6037 0.0000

Atom - Atom Distances bond lengths
Distances in Å
  N1 O2 O3 O4 H5
N1   1.40601.21101.19901.8646
O2 1.4060   2.21072.18580.9640
O3 1.21102.2107   2.19362.1279
O4 1.19902.18582.1936   2.9225
H5 1.86460.96402.12792.9225  

Calculated geometries for HNO3 (Nitric acid).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
N1 O2 H5 102.150 O2 N1 O3 115.083
O2 N1 O4 113.850 O3 N1 O4 131.067

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-O 1
N-O 1
N=O 2

Atom 1 Atom 2
N1 O2
N1 O3
N1 O4
O2 H5
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A'

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
11.950 0.010 12.200   webbook

Electron Affinity (eV)
Electron Affinity unc. reference
0.560 0.170 webbook

Proton Affinity (kJ mol-1)
Proton Affinity unc. Product reference comment
751.4   H2NO3+ 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 1A' Cs True       2.170 NSRDS-NBS10 MW Cs 2 3
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 HNO3 (Nitric acid).
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 1A' Cs True       Cs 2 3

Calculated electric quadrupole moments for HNO3 (Nitric acid).

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squib reference DOI
1960Mil/Mor:1523 Millen, D.J.; Morton, J.R. "The Microwave Spectrum of Nitric Acid." J. Chem. Soc. 1960, 1523-1528 (1960) 10.1039/jr9600001523 
1965Cox/Riv:3106 Cox, A. Peter, Riveros, Jose M., Microwave Spectrum and Structure of Nitric Acid, J. of Chem. Phys., Vol. 42, #9 pgs. 3106-3112 10.1063/1.1696387
1979HUB/HER Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules, Van Nostrand Reinhold Co., 1979 10.1007/978-1-4757-0961-2
Gurvich Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989  
NSRDS-NBS10 R. D. Nelson Jr., D. R. Lide, A. A. Maryott "Selected Values of electric dipole moments for molecules in the gas phase" NSRDS-NBS10, 1967 10.6028/NBS.NSRDS.10
Shim Shimanouchi, T. , Tables of Molecular Vibrational Frequencies, Consolidated Volu 10.6028/NBS.NSRDS.39
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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