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Comparative Thermodynamic Behavior of Physically Restricted Cyclohexane and Cyclohexanone in Porous Silica

Published online by Cambridge University Press:  10 February 2011

S. Amanuel  and
V. M. Malhotra
S. Amanuel
Affiliation:
Department of Physics, Southern Illinois University, Carbondale, Illinois 62901-4401
V. M. Malhotra
Affiliation:
Department of Physics, Southern Illinois University, Carbondale, Illinois 62901-4401
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Abstract

We undertook comparative differential scanning calorimeter (DSC) measurements on cyclohexane (C6H12) and cyclohexanone (C6H10O), physically confined in porous silica of pore radius 4, 7.5, 15, 30, and 62.5 nim, with a view to ascertain how guest fluid-surface host interactions affected the thermodynamic properties of the confined fluids. Our results can be summarized as follows: (a) No distinct signature of freezing or melting transition was observed for the physically confined cyclohexanone, irrespective of whether the bulk was present outside the pores. However, this was not the case for cyclohexane. (b) The solid-to-solid transition temperature of cyclohexane and cyclohexanone inversely scaled with the pore radius of the host porous silica. (c) The cubic-to-orthorhombic transition of cyclohexanone was strongly influenced by whether the bulk fluid was present outside the pores. In the absence of the bulk, the transition temperature was considerably suppressed relative to the bulk transition temperature. However, in the presence of the bulk, the confined and the bulk transitions occurred at the same temperature.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 543: Symposium W – Dynamics in Small Confining Systems IV , 1998 , 45
Copyright
Copyright © Materials Research Society 1999

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References

1. Warnock, J., Awschalom, D. D., and Shafer, M. W., Phys. Rev. Lett. 57, 1753 (1986); D. D. Awschalom and J. Warnock, Phys. Rev. B 35, 6779 (1987); M. B. Ritter, D. D. Awschalom, and M.W. Shafer, Phys. Rev. Lett. 61, 966 (1988); D. D. Awschalom and J. Warnock, in Molecular Dynamics in Restricted Geometries, edited by J. Klafter and J. M. Drake ( Wiley, New York, 1989), pp. 351–369.Google Scholar
2. Mu, R. and Malhotra, V.M., Phys Rev. B 44, 4296 (1991).Google Scholar
3. Jackson, C. L. and McKenna, G B, J. Chem. Phys. 93, 9002 (1990); J. Non-Cryst. Solids 131–133, 221 (1991).Google Scholar
4. Malhotra, V. M., Mu, R., and Natarajan, A., in Dynamics in Small Confining Systems, edited by Drake, J. M., Klafter, J., Kopelman, R., Awschalom, D. D. (Mat. Res. Soc. Proc., 290,Pittsburgh, PA, 1993) pp 121–126.Google Scholar
5. Takei, T., Koninshi, T., Fuji, M., Watanabe, T., and Chikazawa, M., Thermochemica Acta, 267,159 (1993).Google Scholar
6. Molz, E., Wong, A.P. Y., Chan, M. H. W., and Beamish, J. R., Phys. Rev B 48, 5741 (1993).Google Scholar
7. Unruh, K. M., Huber, T. E., and Huber, C.A., Phys. Rev. B 48, 9021 (1993).Google Scholar
8. Timmermans, J., J. Phys. Chem. Solids, 18, 1 (1961).Google Scholar
9. Nakamura, N., Suga, H., and Seki, S., Bull. Chem. Soc. Jpn., 53, 2755 (1980).Google Scholar
10. Wurlifniger, A., Ber. Busenges Phys. Chemie. 79, 1195 (1975); A. Wurliflinger and J. Kreutzenbeck, J. Phys. Chem. Solids, 39, 193 (1978).Google Scholar
11. Mu, R. and Malhotra, V. M., Phys. Rev. B 46, 532 (1992).Google Scholar
12. Mu, R., Xue, Y., Henderson, D. O, and Frazier, D. O., Phys. Rev. B 53, 6041 (1996).Google Scholar