sulphur trioxide

• Formula: O₃S
• Molecular weight: 80.063
• IUPAC Standard InChI: InChI=1S/O3S/c1-4(2)3 Copy

  
• IUPAC Standard InChIKey: AKEJUJNQAAGONA-UHFFFAOYSA-N Copy
• CAS Registry Number: 7446-11-9
• Chemical structure:
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• Other names: Sulfur trioxide
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
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Gas phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of fusion

Vibrational and/or electronic energy levels

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Takehiko Shimanouchi

Symmetry:   D_3h     Symmetry Number σ = 6

Source: Shimanouchi, 1972

Notes

References

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Kondrat'ev and Strizhov, 1985
Kondrat'ev, S.N.; Strizhov, B.V., Zh. Fiz. Khim., 1985, 59, 2933. [all data]

Abercromby and Tiley, 1963
Abercromby, D.C.; Tiley, P.F., 937. The Condensed phases of sulphur trioxide. Part II. Vapour pressure of the liquid at temperatures up to the critical point, J. Chem. Soc., 1963, 4902, https://doi.org/10.1039/jr9630004902 . [all data]

Abercromby and Tiley, 1963, 2
Abercromby, D.C.; Tiley, P.F., The Condensed Phases of Sulphur Trioxide. Part II. Vapour Pressure of the Liquid at Temperatures up to the Critical Point, J. Chem. Soc., 1963, 4902-4904, https://doi.org/10.1039/jr9630004902 . [all data]

Kondrat'ev and Strizhov, 1989
Kondrat'ev, S.N.; Strizhov, B.V., Russ. J. Phys. Chem., 1989, 63, 656. [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume II, J. Phys. Chem. Ref. Data, 1972, 6, 3, 993-1102. [all data]

Notes

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• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  Tfus	Fusion (melting) point
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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