TITLE

Comment on “Glass transition in pure and doped amorphous solid water: An ultrafast microcalorimetry study” [J. Chem. Phys. 125, 094501 (2006)]

AUTHOR(S)
Johari, G. P.
PUB. DATE
October 2007
SOURCE
Journal of Chemical Physics;10/21/2007, Vol. 127 Issue 15, p157101
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
On investigating the data of Chonde et al. [J. Chem. Phys.125, 094501 (2006)], we find that (i) the relaxation time of the test liquid toluene used for determining the ultrafast scans’ reliability was mistaken by several decades and incorrectly plotted, (ii) extrinsic effects had led to an exceptionally broad endotherm showing an enthalpy relaxation occurring implausibly at 500 ps time scale, (iii) enthalpy relaxation times at structural unfreezing and at crystallization temperatures were assumed to be the same, equal to the reciprocal of the heating rate, and (iv) the data for water were incorrectly analyzed. An appropriate analysis would alter their conclusion and would be useful for discussing other ultrafast scans and nanocalorimetry data.
ACCESSION #
27183091

 

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