Chemical Thermodynamics of Tin - Volume 12 - OECD Nuclear ...

198
VIII Group 17 (halogen) compounds and complexes
Hence from these two data,
f
ο
m
Δ H (SnCl 2 , g, 298.15 K) = − (197.5 ± 4.3) kJ·mol –1 .
Other selected data are (Table VIII-17)
ο
–1
C p,m (SnCl 2 , g, 298.15 K) = (54.6 ± 0.1) J·K
–1·mol
ο
S m (SnCl 2 , g, 298.15 K) = (305.9 ± 0.1) J·K –1·mol –1 .
This selection yields:
Δ G (SnCl 2 , g, 298.15 K) = − (206.9 ± 4.3) kJ·mol –1 .
f
ο
m
From mass spectrometric measurements on the vapour above solid and liquid
SnCl 2 [1967KAR/NOV], evidence was found for the existence of the dimer Sn 2 Cl 4 . This
was corroborated by later more detailed measurements of [1987OBR/MUC] and
[2005HIL/ROS]. Partial pressures of monomer and dimer were determined by
[2005HIL/ROS] between 673 and 773 K; their data, when extrapolated, indicate that the
mole fraction of dimer in the gas phase is less than 0.01 at 298 K.
VIII.4.2.2 SnCl 4 (g)
Ideal gas properties of gaseous SnCl 4 were calculated by [1991GUR/VEY] and
[1962ANA] from spectroscopic and structural data. Gurvich and Veyts
[1991GUR/VEY] re-evaluated a large quantity of data, the sources of which are given
in Table VIII-19. The calculations were performed with the use of the rigid rotatorharmonic
oscillator approximation. Reported data appear in Table VIII-20.
Table VIII-19: Data sources for the calculation of ideal gas properties of SnCl 4 .
Data type
References
Electron diffraction [1934BRO/WAL], [1935PAU/BRO], [1931WIE], [1970FUJ/KIM],
[1959LIV/RAO]
Neutron diffraction
[1979GRA/STA], [1977TRI]
Spectroscopic [1973DER], [1968BUR/RUO], [1971CLA/RIP], [1972CLA/RIP],
[1972CLA/RIP2], [1954DEL/FRA], [1967GRI/PAO], [1968KEB/MUL],
[1975STO/BAR], [1972THO/ORV], [1948WEL/CRA], [1978BAB/GRI],
[1984ART/BEA], [1963RUL/WEB], [1964BUT/GER], [1971CLA/WIL],
[1975KON/MUL], [1969LEV], [1963MOS], [1972MUL/KON]
Quantum chemical calculation [1981PIE/BLU]
Electron-gas diffraction [1970FUJ/KIM]
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012