On the Formation of S(3P) and S(1D) During the Thermal Decomposition of COS Behind Shock Waves

  • D. Woiki
  • P. Roth
Conference paper


The formation of ground state S(3 P) and electronically excited S(1 D) atoms was studied during the thermal decomposition of carbonyl sulfide behind reflected shock waves by using atomic resonance absorption spectroscopy (ARAS). The experiments were performed in highly diluted mixtures of Ar with relative concentrations of COS between 4 to 100 ppm in the temperature range 1830 K ≤ T ≤ 3020 K at pressures around 1 bar. The measured slopes of the linear S(3 P) and S(1 D) concentrations divided by the respective concentration of the initial reactants were found to obey the Arrhenius laws:
$$\frac{{d[S{(^3}P)]/dt}}{{[COS][Ar]}}{|_{t \approx 0}} = 2.9 \times {10^{14}} \times \exp (\frac{{63360cal/mol}}{{RT}})c{m^3}mo{l^{ - 1}}{s^{ - 1}}$$
$$\frac{{d[S{(^1}D)]/dt}}{{[COS][Ar]}}{|_{t \approx 0}} = 4.8 \times {10^{12}} \times \exp (\frac{{71800cal/mol}}{{RT}})c{m^3}mo{l^{ - 1}}{s^{ - 1}}$$

These results indicate a fast thermalisation of the partial equilibrium between the S3 P) and S(1 D) states during the non-equilibrium dissociation of COS.

Key words

Thermal decomposition of COS 


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  1. Donovan RJ, Kirch LJ, Husain D (1970) Collisional deactivation of the electronically excited atoms S(31 D 2) and S(31 S 0), by the noble gases. Trans. Faraday Soc. 66: 774CrossRefGoogle Scholar
  2. Hay AJ, Belford RL (1967) High-temperature gas-kinetic study of Carbonyl Sulfide pyrolysis performed with a shock tube and quadrupole mass filter. J. Chem. Physics 47: 3944CrossRefADSGoogle Scholar
  3. Roth P, Just Th (1977) Absorptionsmessungen zur Kinetik der Reaktion CH4 →CH3+OH im Temperaturbereich 1500 ≤ T ≤ 2250 K. Ber. Bunsenges. Phys. Chem. 81: 572Google Scholar
  4. Schecker HG, Wagner HGg (1969) On the thermal decomposition of COS. Intl. J. Chem. Kinet. 1: 541CrossRefGoogle Scholar
  5. Thielen K, Roth P (1987) Resonance absorption measurements of N, O, and H atoms in shock heated HCN/O2/Ar mixtures. Comb. Flame 69: 141CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • D. Woiki
    • 1
  • P. Roth
    • 1
  1. 1.Institut für Verbrennung und GasdynamikUniversität DuisburgDuisburgGermany

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