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Enthalpy Change from Pure Cubic Ice I_c to Hexagonal Ice I_h.

ABSTRACT: The preparation of pure cubic ice without hexagonal stacking faults has been realized only recently by del Rosso et al. ( Nat. Mater. 2020, 19, 663-668) and Komatsu et al. ( Nat. Commun. 2020, 11, 464). With our present calorimetric study on the transition from pure cubic ice to hexagonal ice we are able to clarify the value of the enthalpy change ΔH_c→h to be -37.7 ± 2.3 J mol^-1. The transition temperature is identified as 226 K, much higher than in previous work on ice I_sd. This is due to a catalytic effect of hexagonal faults on the transition, but even more importantly due to a relaxation exotherm that was not properly identified in the past.

SUBMITTER: Tonauer CM

PROVIDER: S-EPMC10240532 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Enthalpy Change from Pure Cubic Ice Ic to Hexagonal Ice Ih.

Tonauer Christina M CM Yamashita Keishiro K Rosso Leonardo Del LD Celli Milva M Loerting Thomas T

The journal of physical chemistry letters 20230525 21

The preparation of pure cubic ice without hexagonal stacking faults has been realized only recently by del Rosso et al. ( Nat. Mater. 2020, 19, 663-668) and Komatsu et al. ( Nat. Commun. 2020, 11, 464). With our present calorimetric study on the transition from pure cubic ice to hexagonal ice we are able to clarify the value of the enthalpy change ΔHc→h to be -37.7 ± 2.3 J mol-1. The transition temperature is identified as 226 K, much higher than in pre ...[more]

PMID: 37227149

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