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Experimental data for HCOOH (Formic acid)

22 02 02 11 45
Other names
Acide formique; Acido formico; Add-F; Ameisensaeure; Aminic acid; Bilorin; Collo-Bueglatt; Collo-Didax; Formic acid; Formic acid, solution; Formira; Formisoton; Formylic acid; Hydrogen carboxylic acid; Kwas metaniowy; Kyselina mravenci; Methanoic acid; Mierenzuur; Myrmicyl;
INChI INChIKey SMILES IUPAC name
InChI=1S/CH2O2/c2-1-3/h1H,(H,2,3) BDAGIHXWWSANSR-UHFFFAOYSA-N OC=O Formic 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 -378.80 0.50 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation -371.51 0.50 kJ mol-1 Gurvich
Entropy (298.15K) entropy 248.87   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 10.90   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 45.80   J K-1 mol-1 Gurvich
Barrier to Internal Rotation 69.4   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' 3570   1966Herzberg       OH str
2 A' 2943   1966Herzberg       CH stretch
3 A' 1770   1966Herzberg       C=O str
4 A' 1387   1966Herzberg       CH bend
5 A' 1229   1966Herzberg       OH bend
6 A' 1105   1966Herzberg       CO stretch
7 A' 625   1966Herzberg       OCO bend
8 A" 1033   1966Herzberg       CH bend
9 A" 638   1966Herzberg       torsion

vibrational zero-point energy: 7150.0 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for HCOOH (Formic acid).
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
2.58548 0.40211 0.34745 1966Herzberg

Calculated rotational constants for HCOOH (Formic acid).
Product of moments of inertia moments of inertia
13262.12amu3Å6   6.07268543189766E-116gm3 cm6
Geometric Data
picture of Formic 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
rCO 1.202   1 3 1966Herzberg
rCO 1.343   1 2 1966Herzberg
rCH 1.097   1 4 1966Herzberg
rOH 0.972   2 5 1966Herzberg
aOCO 124.9 2 1 3 1966Herzberg
aHCO 124.1 3 1 4 1966Herzberg
aHOC 106.3 1 2 5 1966Herzberg

Cartesians
Atom x (Å) y (Å) z (Å)
C1 0.0000 0.4220 0.0000
O2 -1.0338 -0.4353 0.0000
O3 1.1587 0.1022 0.0000
H4 -0.3512 1.4612 0.0000
H5 -0.6482 -1.3276 0.0000

Atom - Atom Distances bond lengths
Distances in Å
  C1 O2 O3 H4 H5
C1   1.34301.20201.09701.8658
O2 1.3430   2.25742.01570.9720
O3 1.20202.2574   2.03142.3041
H4 1.09702.01572.0314   2.8046
H5 1.86580.97202.30412.8046  

Calculated geometries for HCOOH (Formic acid).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
C1 O2 H5 106.300 O2 C1 O3 124.900
O2 C1 H4 111.000 O3 C1 H4 124.100

Bond descriptions


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

Connectivity
Atom 1 Atom 2
C1 O2
C1 O3
C1 H4
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
11.330 0.010 11.500   webbook
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