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II.A.1. (XV.A.)

Listing of experimental data for C5H5NO (4-Pyridinol)

InChI=1/C5H5NO/c7-5-1-3-6-4-2-5/h1-4H,(H,6,7) OC1=CC=NC=C1
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 -30.30 5.30 kJ mol-1 Webbook
Hfg(0K) enthalpy of formation   5.30 kJ 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 (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment

Calculated vibrational frequencies for C5H5NO (4-Pyridinol).
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 C5H5NO (4-Pyridinol).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6

Geometric Data
picture of 4-Pyridinol

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

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å

Calculated geometries for C5H5NO (4-Pyridinol).

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C:C 4
C:N 2
C-O 1
H-C 4
H-O 1

Atom 1 Atom 2
N1 C2
N1 C6
C2 C3
C2 H8
C3 C4
C3 H9
C4 C5
C4 O7
C5 C6
C5 H10
C6 H11
O7 H12

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
9.800 0.030     webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Calculated electric dipole moments for C5H5NO (4-Pyridinol).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for C5H5NO (4-Pyridinol).

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