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TRANSPORT AND GUEST-HOST INTERACTIONS IN
AMORPHOUS AND CRYSTALLINE ICE
by
Sergey Malyk
___________________________________________________________________
A Dissertation Presented to the
FACULTY OF THE GRADUATE SCHOOL
UNIVERSITY OF SOUTHERN CALIFORNIA
In Partial Fulfillment of the
Requirements for the Degree
DOCTOR OF PHILOSOPHY
(CHEMISTRY)
May 2009
Copyright 2009 Sergey Malyk
Object Description
| Title | Transport and guest-host interactions in amorphous and crystalline ice |
| Author | Malyk, Sergey |
| Author email | malyk@usc.edu; smalyk@gmail.com |
| Degree | Doctor of Philosophy |
| Document type | Dissertation |
| Degree program | Chemistry (Chemical Physics) |
| School | College of Letters, Arts and Sciences |
| Date defended/completed | 2009-03-13 |
| Date submitted | 2009 |
| Restricted until | Unrestricted |
| Date published | 2009-03-31 |
| Advisor (committee chair) | Reisler, Hanna |
| Advisor (committee member) |
Wittig, Curt Kresin, Vitaly V. |
| Abstract | Interactions of 13CO2 guest molecules with vapor-deposited porous H2O ices have been examined using temperature programmed desorption (TPD) and Fourier transform infrared (FTIR) techniques. Specifically, the trapping and release of 13CO2 by amorphous solid water (ASW) has been studied.; Samples were prepared by: (i) depositing 13CO2 on top of ASW; depositing 13CO2 underneath ASW; and (iii) co-depositing 13CO2 and H2O during ASW formation. The use of 13CO2 eliminates problems with background 12CO2. Some of the deposited 13CO2 becomes trapped when the ice film is annealed. The amount of 13CO2 trapped in the film depends on the deposition method (i.e., on top of the ASW, underneath the ASW, and co-deposition).; The release of trapped molecules occurs in two stages. The majority of the trapped 13CO2 escapes during the ASW-to-cubic ice phase transition at 165 K and the rest desorbs together with the cubic ice film at 185 K. We speculate that the presence of 13CO2 at temperatures up to at 185 K is due to 13CO2 that is trapped in cavities within the ASW film. These cavities are similar to ones that trap the 13CO2 that is released during crystallization. The difference is that 13CO2 that remains at temperatures up to 185 K does not access escape pathways to the surface during crystallization.; The UHV system was modified to incorporate a novel laser induced desorption (LID) technique in addition to TPD and FTIR. The source of the IR laser radiation at 2.92 µm based on the deuterium gas Raman shifter was developed as a part of the LID setup. Preliminary results of the H2O LID from the ASW films are discussed. Future experiments to investigate the phase transformations of ASW and participation of boundaries in it, dopant transport, and lateral flow of amorphous materials and supercooled liquids are outlined. |
| Keyword | amorphous solid water; ASW; amorphous ice; cubic ice; crystallization; trapping; release; porosity; interstellar ice; laser induced desorption |
| Language | English |
| Part of collection | University of Southern California dissertations and theses |
| Publisher (of the original version) | University of Southern California |
| Place of publication (of the original version) | Los Angeles, California |
| Publisher (of the digital version) | University of Southern California. Libraries |
| Provenance | Electronically uploaded by the author |
| Type | texts |
| Legacy record ID | usctheses-m2041 |
| Contributing entity | University of Southern California |
| Rights | Malyk, Sergey |
| Repository name | Libraries, University of Southern California |
| Repository address | Los Angeles, California |
| Repository email | cisadmin@dots.usc.edu |
| Filename | etd-Malyk-2773 |
| Archival file | uscthesesreloadpub_Volume26/etd-Malyk-2773.pdf |
Description
| Title | Page 1 |
| Contributing entity | University of Southern California |
| Repository email | cisadmin@dots.usc.edu |
| Full text | TRANSPORT AND GUEST-HOST INTERACTIONS IN AMORPHOUS AND CRYSTALLINE ICE by Sergey Malyk ___________________________________________________________________ A Dissertation Presented to the FACULTY OF THE GRADUATE SCHOOL UNIVERSITY OF SOUTHERN CALIFORNIA In Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY (CHEMISTRY) May 2009 Copyright 2009 Sergey Malyk |
