Skip to main content
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.
1. F. Kremer and A. Schönhals, Broadband Dielectric Spectroscopy (Springer-Verlag, Berlin, 2003).
2. R. Böhmer, G. Diezemann, G. Hinze, and E. Rössler, Prog. Nucl. Magn. Reson. Spectrosc. 39, 191 (2001).
3. B. Jakobsen, K. Niss, and N. B. Olsen, J. Chem. Phys. 123, 234511 (2005).
4. D. W. Davidson and R. H. Cole, J. Chem. Phys. 19, 1484 (1951).
5. W. Dannhauser and A. F. Flueckinger, Phys. Chem. Liq. 2, 37 (1970).
6. C. Gainaru, R. Meier, S. Schildmann, C. Lederle, W. Hiller, E. A. Rössler, and R. Böhmer, Phys. Rev. Lett. 105, 258303 (2010).
7. M. Tomsic, A. Jamnik, G. Fritz-Popovski, O. Glatter, and L. Vlcek, J. Phys. Chem. B 111, 1738 (2007).
8. B. Jakobsen, C. Maggi, T. Christensen, and J. C. Dyre, J. Chem. Phys. 129, 184502 (2008).
9. H. Huth, L.-M. Wang, C. Schick, and R. Richert, J. Chem. Phys. 126, 104503 (2007).
10. O. E. Kalinovskaya and J. K. Vij, J. Chem. Phys. 112, 3262 (2000).
11. A. R. Brás, J. P. Noronha, A. M. Antunes, M. M. Cardoso, A. Schönhals, F. Affouard, M. Dionísio, and N. T. Correia, J. Phys. Chem. B 112, 1108711099 (2008).
12. A. R. Brás, E. G. Merino, P. D. Neves, I. M. Fonseca, M. Dionísio, A. Schönhals, and N. T. Correia, J. Phys. Chem. C 115, 46164623 (2011).
13. K. Adrjanowicz, K. Kaminski, Z. Wojnarowska, M. Dulski, L. Hawelek, S. Pawlus, M. Paluch, and W. Sawicki, J. Phys. Chem. B 114, 65796593 (2010).
14. K. Adrjanowicz, Z. Wojnarowska, M. Paluch, and J. Pionteck, J. Phys. Chem. B 115, 45594567 (2011).
15. K. Adrjanowicz, A. Grzybowski, K. Kaminski, and M. Paluch, Mol. Pharm. 8, 19751979 (2011).
16. F. Affouard and N. T. Correia, J. Phys. Chem. B 114, 1139711402 (2010).
17.See supplementary material at for detailed description of the synthesis procedure, chemical purity analysis, and dielectric studies. [Supplementary Material]
18. M. L. Vueba, M. E. Pina, and L. A. Batista de Carvalho, J. Pharm. Sci. 97, 845859 (2008).
19. I. Bratu, A. Hernanz, J. M. Gavira, and Gh. Bora, Rom. J. Phys. 50, 10631069 (2005).
20. J. Grdadolnik, Vib. Spectrosc. 31, 279288, (2003)
21. D. B. Parry, M. G. Samant, and O. R. Melroy, Appl. Spectrosc. 45, 9991007 (1991).

Data & Media loading...


Article metrics loading...



In this Communication, we present experimental studies that put new insight into the puzzling nature of the Debye relaxation found in the supercooled liquid state of racemic ibuprofen. The appearance of D-relaxation in the loss spectra of non-hydrogen bonding methylated derivate of ibuprofen has proven that Debye relaxation is related solely with conformational changes of the carboxyl group, termed in this paper as synperiplanar-antiperiplanar. Our studies indicate that the presence of hydrogen bonding capabilities is not here the necessary condition to observe Debye process, however, their occurrence might strongly influence α- and D-relaxations dynamics. Interestingly, the activation energy of the D-process in ibuprofen methyl ester on approaching T was found to be perfectly consistent with that reported for ibuprofen by Affouard and Correia [J. Phys. Chem. B114, 11397–11402 (Year: 2010)] (∼39 kJ/mol). Finally, IR measurements suggest that the equilibrium between conformers concentration depends on time and temperature, which might explain why the appearance of D-relaxation in supercooled ibuprofen depends on thermal history of the sample.


Full text loading...


Access Key

  • FFree Content
  • OAOpen Access Content
  • SSubscribed Content
  • TFree Trial Content
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd