2,3-dithiabutane: low temperature heat capacity, heat of fusion, heat of vaporization, vapor pressure, entropy, and thermodynamic functions

Journal Article · Thu Jun 01 00:00:00 EDT 1950 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja01162a021· OSTI ID:7219938

Scott, D W; Finke, H L; Gross, M E; Guthrie, G B; Huffman, H M

The heat capacity of 2,3-dithiabutane has been measured over the temperature range 13 to 350/sup 0/K The triple point (188.44/sup 0/K) and heat of fusion (2197.1 = 0.1 cal./mole) were determined. The vapor pressure has been measured over the temperature range 0 to 130/sup 0/ and the following equation was found to fit the vapor pressure data: log/sub 10/ p (mm.) = 6.97792 - 1346.342/(l + 218.863). The normal boiling point is 109.75/sup 0/; the heat of vaporization calculated from the vapor pressure data is 9,181 = 75 cal./mole at 298.16/sup 0/K. The entropy of the liquid is 56.26 = 0.10 cal./deg./mole and the entropy of the ideal gas at one atmosphere pressure is 80.54 = 0.30 cal./deg./mole, both at 298.16/sup 0/K. A vibrational assignment has been made for 2,3-dithiabutane with the aid of normal coordinate calculations. Internal rotation about the S--S bond is highly restricted; a 9500 cal./mole twofold potential barrier was used for thermodynamic calculations. The barrier height for methyl rotation was found to be 1140 cal./mole. Values of the free energy function, heat content, entropy, and heat capacity were calculated by the methods of statistical mechanics for selected temperatures up to 1000/sup 0/K.

• Research Organization: Bureau of Mines, Bartlesville, OK
• OSTI ID: 7219938
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 72:6; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
CHALCOGENIDES
ENTHALPY
ENTROPY
FUSION HEAT
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHYSICAL PROPERTIES
SPECIFIC HEAT
SULFIDES
SULFUR COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION HEAT
VAPOR PRESSURE
VAPORIZATION HEAT