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Experimental data for HI+ (Hydrogen iodide cation)

22 02 02 11 45
Other names
Hydriodic acid; Hydroiodic acid; hydrogen iodide;
INChI INChIKey SMILES IUPAC name
InChI=1S/HI/h1H XMBWDFGMSWQBCA-UHFFFAOYSA-N I hydrogen iodide
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 26.50 0.10 kJ mol-1 CODATA
Hfg(0K) enthalpy of formation 28.68 0.10 kJ mol-1 CODATA
Entropy (298.15K) entropy 206.59   J K-1 mol-1 webbook
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 8.66   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 29.16   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 Σ 2230 2309 webbook      

Detailed diatomic data
ωe ωexe ωeye Be αe ZPE reference
2309.014 39.6435 -0.02 6.426365 0.16886 webbook

vibrational zero-point energy: 1114.8 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for HI+ (Hydrogen iodide cation).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
  6.42637 6.42637 webbook

Calculated rotational constants for HI+ (Hydrogen iodide cation).
Product of moments of inertia moments of inertia
2.623199amu Å2   4.355992E-40gm cm2
Geometric Data
picture of Hydrogen iodide cation

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
rHI 1.609 0.000 1 2 NISTdiatomic re

Cartesians
Atom x (Å) y (Å) z (Å)
I1 0.0000 0.0000 0.0000
H2 0.0000 0.0000 1.6092

Atom - Atom Distances bond lengths
Distances in Å
  I1 H2
I1   1.6092
H2 1.6092  

Calculated geometries for HI+ (Hydrogen iodide cation).

Bond descriptions


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

Connectivity
Atom 1 Atom 2
I1 H2
Electronic energy levels (cm-1) An error occurred on the server when processing the URL. Please contact the system administrator.

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