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Experimental data for CHONH2 (formamide)

Other names
Amid kyseliny mravenci; Formimidic acid; formamide; Formimidic acid; Methanamide; Amid kyseliny mravenci; Methanamide; Carbamaldehyde; Carbamaldehyde;
InChI=1S/CH3NO/c2-1-3/h1H,(H2,2,3) ZHNUHDYFZUAESO-UHFFFAOYSA-N NC=O formamide
InChI=1/CH3NO/c2-1-3/h1H,(H2,2,3)/f/h2H2 ZHNUHDYFZUAESO-RZDQGJFANA-N NC=O formamide
State Conformation
1A' Planar
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 -186.00   kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy     J K-1 mol-1  
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity     kJ mol-1  
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' 3564   1983Sug/Ham:1045      
2 A' 3439          
3 A' 2854          
4 A' 1754          
5 A' 1577          
6 A' 1390          
7 A' 1258          
8 A' 1046          
9 A' 581          
10 A" 1021          
11 A" 603          
12 A" 289          

vibrational zero-point energy: 9687.6 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for CHONH2 (formamide).
Gas-phase IR spectra can be found in the NIST Chemistry Webbook here.
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
2.42556 0.37939 0.32802 1974Hir/Sug:251

Calculated rotational constants for CHONH2 (formamide).
Product of moments of inertia moments of inertia
15870.78amu3Å6   7.26718584902227E-116gm3 cm6
Geometric Data
picture of formamide

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
rCN 1.350   1 3 1974Hir/Sug:251
rNH 1.001   3 6 1974Hir/Sug:251 cis
rNH 1.001   3 5 1974Hir/Sug:251 trans
rCO 1.210   1 2 1974Hir/Sug:251
rCH 1.090   1 4 1974Hir/Sug:251
aHNH 121.6 5 3 6 1974Hir/Sug:251
aHNC 118.5 1 3 6 1974Hir/Sug:251 cis H
aHNC 120 1 3 5 1974Hir/Sug:251 trans
aNCO 124.7 2 1 3 1974Hir/Sug:251
aHCN 112.7 3 1 4 1974Hir/Sug:251
aHCO 122.5 2 1 4 1974Hir/Sug:251

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.4165 0.0000
O2 1.1942 0.2217 0.0000
N3 -0.9373 -0.5551 0.0000
H4 -0.4299 1.4182 0.0000
H5 -0.6608 -1.5171 0.0000
H6 -1.9020 -0.2881 0.0000

Atom - Atom Distances bond lengths
Distances in Å
  C1 O2 N3 H4 H5 H6
C1   1.21001.35001.09002.04352.0283
O2 1.2100   2.26862.01732.54253.1379
N3 1.35002.2686   2.03741.00101.0010
H4 1.09002.01732.0374   2.94442.2535
H5 2.04352.54251.00102.9444   1.7467
H6 2.02833.13791.00102.25351.7467  

Calculated geometries for CHONH2 (formamide).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
C1 N3 H5 120.000 C1 N3 H6 118.500
O2 C1 N3 124.700 O2 C1 H4 122.500
N3 C1 H4 112.800 H5 N3 H6 121.500

Bond descriptions

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

Atom 1 Atom 2
C1 O2
C1 N3
C1 H4
N3 H5
N3 H6
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
10.160 0.060     webbook

Electron Affinity (eV)
Electron Affinity unc. reference
0.017   webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
x y z total
      3.730 NSRDS-NBS10  

Calculated electric dipole moments for CHONH2 (formamide).
Electric quadrupole moment quadrupole
Quadrupole (D Å) Reference comment
xx yy zz
-0.300 3.400 -3.100 1971Fly/Ben:225 Qxx=3.4+-0.4, Qyy=-0.3+-0.5, Qzz=-3.1+-0.8

Calculated electric quadrupole moments for CHONH2 (formamide).
Electric dipole polarizability (Å3) polarizability
alpha unc. Reference
4.080   1998Gus/Rui:163

Calculated electric dipole polarizability for CHONH2 (formamide).

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squib reference DOI
1971Fly/Ben:225 WH Flygare, RC Benson "The molecular Zeeman effect in diamagnetic molecules and the determination of molecular magnetic moments (g values), magnetic susceptibilities, and molecular quadrupole moments" Mol. Phys. 1971, 20 (2), 225-250 10.1080/00268977100100221
1974Hir/Sug:251 E Hirota, R Sugisaki "Molecular Structure and Internal Motion of Formamide from Microwave Spectrum" J. Mol. Spec. 49, 251, 1974 10.1016/0022-2852(74)90274-4
1983Sug/Ham:1045 Y Sugawara, Y Hamada, M Tsuboi, " Vibration-Rotation Spectra of Formamides" Bull. Chem. Soc. Jpn. 56, 1045, 1983 10.1246/bcsj.56.1045
1998Gus/Rui:163 M Gussoni, R Rui, G Zerbi "Electronic and relaxation contribution to linear molecular polarizability. An analysis of the experimental values" J. Mol. Struct. 447 (1998) 163-215 10.1016/S0022-2860(97)00292-5
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
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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