Jump to main content
Jump to site search

Issue 3, 2010
Previous Article Next Article

Reversibility and isotope effect of the calorimetric glass → liquid transition of low-density amorphous ice

Author affiliations

Abstract

We here report differential scanning calorimetry (DSC) scans recorded by repeatedly heating the H2O (D2O) low density amorph (LDA) which was made by isothermal decompression of very high-density amorphous ice (VHDA) at 140 K from 1.1 to 0.006 GPa. These DSC scans show a glass → liquid transition endotherm with an onset temperature (Tg) of ≈137 (140) K at a heating rate of 30 K min−1 accompanied by an increase in heat capacity of ≈1.7 (1.5) J K−1 mol−1. We establish the reversibility of this effect by thermally cycling between its glassy state below 137 K and its highly viscous liquid state at 149 K. All calorimetric signatures, including H/D isotope effect, are highly similar to the signatures in hyperquenched glassy water (HGW). We argue that the observation of almost identical calorimetric traces for HGW and LDA implies that there is no need to reassign HGWs Tg to higher temperatures provided that the viscous liquid state connected to both LDA and HGW behaves as an ideally “strong” liquid in the Angell classification. We furthermore show that LDA prepared by isothermal decompression of VHDA is more crystallization-resistant than LDA made from high-density amorphous ice (HDA) by isobaric warming. We suggest that the former route via VHDA removes “nanocrystalline remnants” in LDA which are still present in the latter after pressure-amorphization of hexagonal ice to HDA at 77 K.

Graphical abstract: Reversibility and isotope effect of the calorimetric glass → liquid transition of low-density amorphous ice

Back to tab navigation

Publication details

The article was received on 27 Aug 2009, accepted on 23 Oct 2009 and first published on 20 Nov 2009


Article type: Paper
DOI: 10.1039/B917662D
Citation: Phys. Chem. Chem. Phys., 2010,12, 708-712
  •   Request permissions

    Reversibility and isotope effect of the calorimetric glass → liquid transition of low-density amorphous ice

    M. S. Elsaesser, K. Winkel, E. Mayer and T. Loerting, Phys. Chem. Chem. Phys., 2010, 12, 708
    DOI: 10.1039/B917662D

Search articles by author

Spotlight

Advertisements