The Effect of Underlying Substrate on the Crystallization Kinetics of Dense Amorphous Solid Water Films
The crystallization kinetics of thin, dense amorphous solid water films deposited on crystalline ice and Pt(111) substrates are investigated. A dramatic acceleration of the crystallization rate is observed for amorphous films on crystalline ice substrates. The acceleration originates from the absence of the nucleation process on the crystalline ice substrate which serves as a 2-dimensional nucleus for the growth of the crystalline phase. This contrasts with the crystallization on a Pt(111) substrate which proceeds via bulk nucleation and 3-dimensional growth. Activation energies for growth and nucleation are determined to be 56 and 140 kJ/mol, respectively using the apparent activation energies measured on crystalline ice and Pt(111) substrates. For amorphous films deposited on crystalline ice substrates, the crystallization rate decreases rapidly with increasing distance from the crystalline ice substrate most probably due to crystallization induced cracking of the films.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 913616
- Report Number(s):
- PNNL-SA-32228; JCPSA6; KC0301020; TRN: US200802%%720
- Journal Information:
- Journal of Chemical Physics, 112(13):5932-5941, Vol. 112, Issue 13; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
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