Molecule
Name
Methane
IUPAC name
Methane
Secondary names
Methyl hydride, CH4
InChI
InChI=1S/CH4/h1H4
InChI key
VNWKTOKETHGBQD-UHFFFAOYSA-N
CAS number
74-82-8
Comments
natural $CH_4$
Formula
$CH_4$
Chemical formula
CH4
Structural formula
[CH4]
Charge
0
Unpaired electrons
0
  Atom Name Number
$C$ Carbon 1
$H$ Hydrogen 4
Relations
  • no
Isotope mixture type
terrestrial abundance
Isotopes
  Isotope Mole fraction
$^{12}CH_4$ 0.988845
$^{13}CH_4$ 0.010695079
$^{12}CH_3D$ 0.000454921
Spin type
equilibrated
Spin quantum numbers
0, 1, 2
Molar mass
16.04249891 $g/mol$
State STP
gas
Protic
aprotic
Polarity
nonpolar
Dipole
0.0 $D$
Molecule symmetry
Td
Case
spherical-top
Vibrations number
4
Vibrations
Label Mode Bond Symmetry Degeneracy Fundamental frequency Observed frequency Observed frequency Harmonic frequency Activity IR Activity Raman Strength Comments
V1 stretching sym. $CH_4$ $A_{1}$ no 2917.0 3025.5 inactive active ia Raman: 2917.0 $cm^{-1}$ (gas)
V2 deformation $CH_4$ $E$ double 1534.0 1533.0 1582.7 inactive active m inactif, but Coriolis interaction with V4 - Raman: 2917.0 $cm^{-1}$ (gas)
V3 stretching $CH_4$ $F_{2}$ triple 3018.9 3156.8 active active vs Raman: 3019.5 $cm^{-1}$ (gas)
V4 deformation $CH_4$ $F_{2}$ triple 1306.2 1367.4 active inactive vs
Comments
Vibrations of the main isotope: $^{12}CH_4$. Harmonic frequencies from Gray and Robiette (1979) - Data from NIST Chemistry WebBook
Publications
Chemical bonds
  Bond Number
$\geq C-H$ 4