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Experimental data for C5H12 (Butane, 2-methyl-)

22 02 02 11 45
Other names
1,1,2-Trimethylethane; 2-Methylbutane; Butane, 2-methyl-; Ethyldimethylmethane; Isoamylhydride; iso-C5H12; iso-Pentane; isopentane;
INChI INChIKey SMILES IUPAC name
InChI=1S/C5H12/c1-4-5(2)3/h5H,4H2,1-3H3 QWTDNUCVQCZILF-UHFFFAOYSA-N CC(C)CC isopentane
State Conformation
1A C1
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 -153.70   kJ mol-1 TRC
Hfg(0K) enthalpy of formation -119.70   kJ mol-1 TRC
Entropy (298.15K) entropy 343.74   J K-1 mol-1 TRC
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 22.01   kJ mol-1 TRC
Heat Capacity (298.15K) heat capacity 118.90   J K-1 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 Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference

Calculated vibrational frequencies for C5H12 (Butane, 2-methyl-).
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

Calculated rotational constants for C5H12 (Butane, 2-methyl-).
Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6
Geometric Data
picture of Butane, 2-methyl-

Point Group C1


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

Cartesians
Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å
 

Calculated geometries for C5H12 (Butane, 2-methyl-).

Bond descriptions


Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 12
C-C 4

Connectivity
Atom 1 Atom 2
H1 C4
H2 C4
H3 C4
C4 C7
H5 C7
H6 C7
C7 C9
H8 C9
C9 C13
C9 C17
H10 C13
H11 C13
H12 C13
H14 C17
H15 C17
H16 C17
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
10.320 0.050 10.940   webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
State Config State description Conf description Exp. min. Dipole (Debye) Reference comment Point Group Components
x y z total dipole quadrupole
1 1 1A C1 True       0.130 NSRDS-NBS10 DT C1 3 5
Experimental dipole measurement abbreviations: MW microwave; DT Dielectric with Temperature variation; DR Indirect (usually an upper limit); MB Molecular beam
Calculated electric dipole moments for C5H12 (Butane, 2-methyl-).
Electric quadrupole moment quadrupole
State Config State description Conf description Exp. min. Quadrupole (D Å) Reference comment Point Group Components
xx yy zz dipole quadrupole
1 1 1A C1 True       C1 3 5

Calculated electric quadrupole moments for C5H12 (Butane, 2-methyl-).
Electric dipole polarizability (Å3) polarizability
alpha unc. Reference
8.770   1998Gus/Rui:163

Calculated electric dipole polarizability for C5H12 (Butane, 2-methyl-).
References
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squib reference DOI
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
TRC Frenkel, M; Marsh, K.N.; Wilhoit, R.C.; Kabo, G.J.; Roganov, G.N.,Thermodynamics of Organic Compounds in the Gas State,Thermodynamics Research Center, College Station, TX, 1994  
webbook NIST Chemistry Webbook (http://webbook.nist.gov/chemistry) 10.18434/T4D303

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