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 SO2
Structure and atomic composition
Formula
SO2
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
32S16O2 0.94529
32S16O17O 0.0007202
32S16O18O 0.003885
32S18O2 3.992e-06
33S16O2 0.007464
33S16O17O 0.0003751
33S16O18O 3.067e-05
34S16O2 0.04229
34S16O17O 0.002158
34S16O18O 0.0001738
36S16O2 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. SO2 A1 no 1151.0 1151.4 active active s Raman: 1150.5 cm−1 (s)
V2 bending SO2 A1 no 518.0 517.7 active active s Raman: 524.5 cm−1 (liq, w)
V3 stretching asym. SO2 B1 no 1362.0 1361.8 active active s Raman: 1336 cm−1 (liq, w)
Comments
Vibrations of the main isotope: 32S16O2. Data from NIST Chemistry WebBook
Publications
Chemical bonds
  Bond Number
=S=O 2