THERMOCHEMICAL INVESTIGATIONS OF COORDINATOCLATHRATES WITH FLUORENYL GROUPS

The interactions of clathrate-forming host compounds with different so lvent vapours in a concentration range up to 1500 ppm were investigate d with a thermal sensor. The used thermopile chip gave the possibility to record small amounts of heat power with short response times. The correlation between the signal parameters (area, height) and concentra tion of vapour is linear. The differences between the sensitivities of the different host-guest combinations are significant. The determinat ion of the amount of guest molecules, included by the host compounds, as a function of the partial pressure leads to the result that clathra te formation only takes place near saturation pressure. The same perce ption was applied for measurements of the heat of sorption as a functi on of the weight of the layer on the thermopile chip. The reaction see ms to be controlled by a surface process. (C) 1998 Elsevier Science B. V.