National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Listing of experimental data for Fe(CO)5 (Iron pentacarbonyl)

Other names
Iron carbonyl; Pentacarbonyl iron;
State Conformation
1A1 C4V
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
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
1 A1' 2121 1972Jon/McD:2050      
2 A1' 2042 1972Jon/McD:2050      
3 A1' 443 1972Jon/McD:2050      
4 A1' 413 1972Jon/McD:2050      
5 A2' 383 1972Jon/McD:2050      
6 A2" 2034 1972Jon/McD:2050      
7 A2" 619 1972Jon/McD:2050      
8 A2" 429 1972Jon/McD:2050      
9 A2" 100 1972Jon/McD:2050      
10 E' 2013 1972Jon/McD:2050      
11 E' 645 1972Jon/McD:2050      
12 E' 543 1972Jon/McD:2050      
13 E' 474 1972Jon/McD:2050      
14 E' 105 1972Jon/McD:2050      
15 E' 74 1972Jon/McD:2050      
16 E" 488 1972Jon/McD:2050      
17 E" 375 1972Jon/McD:2050      
18 E" 97 1972Jon/McD:2050      

Calculated vibrational frequencies for Fe(CO)5 (Iron pentacarbonyl).
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 Fe(CO)5 (Iron pentacarbonyl).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of Iron pentacarbonyl

Point Group D3h

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 Fe(CO)5 (Iron pentacarbonyl).

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-Fe 5
C#O 5


Atom 1 Atom 2
Fe1 C2
Fe1 C3
Fe1 C4
Fe1 C5
Fe1 C6
C2 O7
C3 O8
C4 O9
C5 O10
C6 O11
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Calculated electric dipole moments for Fe(CO)5 (Iron pentacarbonyl).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for Fe(CO)5 (Iron pentacarbonyl).

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squib reference DOI
1972Jon/McD:2050 LH JOnes, RS McDowell, M Goldblatt, BI Swanson "Potential Constants of Iron Pentacarbonyl from Vibrational Spectra of Isotopic Species" J. Chem. Phys. 57(5) 2050 1972 10.1063/1.1678529

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