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New Limits of Secondary β-Relaxation


New Limits of Secondary β-Relaxation

Satya N Tripathy et al. Sci Rep.


Glass is an ultraviscous liquid that ceases to flow on a laboratory timescale but continues to relax on a geological timescale. Quintessentially, it has become hopeless for humans to explore the equilibrium behavior of glass, although the technology of glass making witness a remarkable advance. In this work, we propose a novel thermodynamic path to prepare a high density amorphous state of matter (carvedilol dihydrogen phosphate) using high pressure. In addition, we provide the impeccable experimental evidence of heterogeneous nature of secondary β-relaxation and probe its properties to understand the various aspects of pressure densified glass, such as dynamics, packing and disorder. These features are expected to provide new horizons to glass preparation and functional response to pharmaceutical applications.

Conflict of interest statement

The authors declare no competing financial interests.


Figure 1
Figure 1. The specific volume (Vsp) of carvedilol dihydrogen phosphate as a function of temperature using two thermodynamic paths.
Inset: Schematic illustration of thermodynamic paths leading to various glassy structures (OG - ordinary glass using path A, DG - pressure densified glass using path B). T1 represent the temperature of examination point whereas T2 indicate the temperature corresponding to isothermal compression of OG to attain glassy state. The DG sample is obtained after following path B with decompression at T = T1. Both the samples OG and DG are compared at (T1, p = 0.1 MPa).
Figure 2
Figure 2
(a) Relaxation map of carvedilol dihydrogen phosphate. The open red and blue circles represent the conductivity relaxation time (τσ) for OG and DG respectively estimated from dielectric modulus spectra. The gray and pink star symbols refer to OG sample and illustrate viscosity data (η) and structural relaxation times (τα) which were determined from temperature modulated differential scanning calorimetry (TMDSC). The red and blue stars depict the aging time (τage) for OG and DG respectively. The black open triangles show the temperature dependence behavior of slower secondary β-relaxation times (τβ′) of OG. The blue and red circles present the faster secondary β-relaxation times (τβ″) of DG and OG respectively. The inset represent the comparison plot of β-spectra in dielectric modulus representation (M″) for OG and DG at T = 183 K and p = 0.1 MPa. (b) time temperature superposition of β″-modulus spectra at T = 183 K and p = 0.1 MPa of OG and DG (c) DSC traces obtained for both the paths with heating rate equals to 10 K/min. The solid blue and red lines show the behavior of DG and OG glasses, respectively. Reprinted (η and τα data) with permission from Wojnarowska, Z., Wang, Y., Pionteck, J., Grzybowska, K., Sokolov, A.P., Paluch, M. Phys. Rev. Lett. 111, 225703-225703, 2013. Copyright 2013 by the American Physical Society. The τage values are reprinted (adapted) with permission from Wojnarowska, Z., Roland, C.M., Kolodziejczyk, K., Swiety-Pospiech, A., Grzybowska, K., Paluch, M. J. Phys. Chem. Lett., 3(10), 1238–1241, 2012. Copyright 2012 American Chemical Society.

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    1. Ediger M. D., Angell C. A. & Nagel S. R. Supercooled liquids and glasses. J. Phys. Chem. 100, 13200–13212 (1996).
    1. Angell C. A., Ngai C. A., McKenna G. B., McMillan P. F. & Martin S. W. Relaxation in glassforming liquids and amorphous solids. J. Appl. Phys. 88, 3113–3157 (2000).
    1. Kremer F. & Schoenhals A. Broadband dielectric spectroscopy. (Springer, Berlin) (2003).
    1. McCrum N. G., Read B. E. & Williams G. Anelastic and dielectric effects in polymeric solids. (Dover, New York) (1991).
    1. Floudas G., Paluch M., Grzybowski A. & Ngai K. L. Molecular dynamics of glass forming systems: Effect of pressure. (Springer, New York) (2011).

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