Phys. Chem. Chem. Phys., 2003, 5

Additions and corrections

The low-temperature dynamics of recovered ice XII as studied by differential scanning calorimetry: a comparison with ice V

Christoph G. Salzmann, Ingrid Kohl, Thomas Loerting, Erwin Mayer and Andreas Hallbrucker

Phys. Chem. Chem. Phys., 2003, 5, 3507 (DOI: 10.1039/b305624d). Amendment published 24th July 2003.

Omit the passage from page 3514, column 1, lines 28 to 36:

We note that additional effects can occur when a sample is cooled under pressure and the DSC scan of the recovered sample recorded on subsequent heating at 1 bar which is the experimental setup used here. This is shown for polystyrene in Fig. 4.45 of ref. 37. Summarizing we cannot unambiguously decide whether the pronounced exotherm with Tmin of 133 K shown in Fig. 6, curves (a) and (b), and the weak exothermic feature near Tonset in Fig. 2, curves (b) and (c), have the same origin.

Omit the passage from page 3514, column 2, line 61 to page 3515, column 1, line 7:

This shift of Tonset to lower temperature on second heating, or after annealing, could be caused by diffusion of impurities into the ice V lattice, thus acting as extrinsic Bjerrum defects and lowering the Arrhenius energy. The effect of dissolved impurities such as CO2 or N2 gas onto the dielectric relaxation time and Arrhenius energy had been ascertained for ice Ih, and similar conclusions have been drawn for interpreting the dielectric relaxation time of ice V.42 These extrinsic Bjerrum defects could be gaseous N2 because, when the recovered ice V sample is filled under liquid N2 into the DSC cell and the lid screwed on, considerable pressure buildup of gaseous N2 could occur on heating and the N2 penetrate the ice V lattice. Similar pressure buildup is unlikely in the high pressure vessel on cooling ice V to 77 K after its formation in the ice V domain.

Insert the following passage at page 3516, column 2, line 37, before "A further complication":

Further support for our reassignment of the endothermic step to ice XII instead of LDA comes from Tmin of the intense exotherm caused by the phase transition to ice Ic: this was reported in our previous studies of pressure-amorphized ice Ih or ice Ic as 160 K for heating at a rate of 30 K min-1 (cf. Table 1 in ref. 22). However, from this study it follows that this Tmin is the value for the ice XII to ice Ic transition whereas Tmin of the LDA to ice Ic transition is at 171 K.

To the acknowledgements should be added:

We are grateful to Prof. G. P. Johari for reading and commenting the manuscript.

The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.

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