Standard reference material proposed for enthalpy-of-sublimation measurements. A comparative study of the standard molar enthalpy of sublimation of Fe(c-C5H5)2(ferrocene) by calorimetry and knudsen-effusion techniques

The standard molar enthalpy of sublimation ofη5-bis-pentamethylcyclopentadienyl iron measured with an electrically calibrated vacuum-drop sublimation microcalorimetric apparatus

“…(12,18,41,(45)(46)(47)(48)(49)(50)(51)(52) The tests with benzoic acid and ferrocene indicate that the apparatus described in this paper, enables accurate determinations of the enthalpies of sublimation with very small amounts of sample compared to those used in our Knudsen effusion apparatus. (12)(13)(14) The standard molar enthalpy of sublimation of η 5 -bis-pentamethylcyclopentadyenyl iron, at T = 362.0 K, derived from the data in 30 Fe as a function of the temperature was also measured in this work, using a DSC 121 from Setaram and the procedure previously described.…”

Thermochemistry of benzoquinones

“…The device, experimental procedure and analysis data have previously been described [28][29][30]. The Knudsen method allows the determination of the vapour pressure, from measurements at different temperature T , of the rate of mass loss ðdm=dtÞ of a substance, through an orifice of a given area A from an effusion cell.…”

Enthalpies of sublimation of ferrocene and nickelocene measured by calorimetry and the method of Langmuir

“…Then the heat of sublimation can be derived from the dependence of the vapour pressure on the temperature using the Clausius-Clapeyron equation. Examples of indirect techniques are Knudsen's effusion [8][9][10][11] and Langmuir's method [12][13][14][15][16][17][18], which is adopted in this work.…”