Molecule
Name
Sulfur dioxide
IUPAC name
Sulfur dioxide
Secondary names
Sulfurous anhydride, Sulfurous oxide, Sulfur oxide, Sulphur dioxide, Sulfurous acid anhydride, SO2
InChI
InChI=1S/O2S/c1-3-2
InChI key
RAHZWNYVWXNFOC-UHFFFAOYSA-N
CAS number
7446-09-5
Comments
natural $SO_2$
Structure and atomic composition
Formula
$SO_2$
Chemical formula
SO2
Structural formula
O=S=O
Charge
0
Unpaired electrons
0
  Atom Name Number
$S$ Sulfur 1
$O$ Oxygen 2
Relations
  • no
Isotope mixture type
terrestrial abundance
Isotopes
  Isotope Mole fraction
$^{32}S^{16}O_2$ 0.94529
$^{32}S^{16}O^{17}O$ 0.0007202
$^{32}S^{16}O^{18}O$ 0.003885
$^{32}S^{18}O_2$ 3.992e-06
$^{33}S^{16}O_2$ 0.007464
$^{33}S^{16}O^{17}O$ 0.0003751
$^{33}S^{16}O^{18}O$ 3.067e-05
$^{34}S^{16}O_2$ 0.04229
$^{34}S^{16}O^{17}O$ 0.002158
$^{34}S^{16}O^{18}O$ 0.0001738
$^{36}S^{16}O_2$ 0.00675
Spin type
unique
Spin quantum numbers
0
Molar mass
64.06359709 $g/mol$
State STP
gas
Protic
aprotic
Polarity
polar
Dipole
1.63305 $D$
Molecule symmetry
C2v
Case
nonlinear-triatomic
Vibrations number
3
Vibrations
Label Mode Bond Symmetry Degeneracy Fundamental frequency Observed frequency Observed frequency Harmonic frequency Activity IR Activity Raman Strength Comments
V1 stretching sym. $SO_2$ $A_{1}$ no 1151.0 1151.4 active active s Raman: 1150.5 $cm^{-1}$ (s)
V2 bending $SO_2$ $A_{1}$ no 518.0 517.7 active active s Raman: 524.5 $cm^{-1}$ (liq, w)
V3 stretching asym. $SO_2$ $B_{1}$ no 1362.0 1361.8 active active s Raman: 1336 $cm^{-1}$ (liq, w)
Comments
Vibrations of the main isotope: $^{32}S^{16}O_2$. Data from NIST Chemistry WebBook
Publications
Chemical bonds
  Bond Number
$=S=O$ 2