Density and birefringence of a highly stable α,α,β-trisnaphthylbenzene glass

TitleDensity and birefringence of a highly stable α,α,β-trisnaphthylbenzene glass
Publication TypeJournal Article
Year of Publication2012
AuthorsDalal, S. S., A. Sepulveda, G. K. Pribil, Z. Fakhraai, and M. D. Ediger
JournalJournal of Chemical Physics
Volume136
Pagination10
Date PublishedMay
Type of ArticleArticle
ISBN Number0021-9606
Accession NumberWOS:000304818400033
KeywordsDEPOSITION, GROWTH, INDOMETHACIN, MOLECULAR-ORIENTATION, SPECTROSCOPIC ELLIPSOMETRY, SUPERCOOLED LIQUID, THERMAL-EXPANSION, THIN POLYMER-FILMS, TRANSITION, VAPOR
Abstract

Spectroscopic ellipsometry has been used to understand the properties of alpha,alpha,beta-trisnaphthylbenzene (alpha alpha beta-TNB) glasses vapor-deposited at a substrate temperature of 295 K (0.85 T-g). In a single temperature ramping experiment, a range of properties of the as-deposited glass can be measured, including density, fictive temperature, onset temperature, thermal expansion coefficient, and birefringence. The vapor-deposited alpha alpha beta-TNB glass is 1.3% more dense than the ordinary glass prepared by cooling at 1 K/min, is found to be birefringent, has a fictive temperature 35 K below that of the ordinary glass, and an onset temperature 20 K above that of the ordinary glass. The thermal expansion coefficient of the vapor-deposited alpha alpha beta-TNB glass is 14% lower than that of the ordinary glass, indicating that lower portions of the potential energy landscape have more harmonic potential minima than the parts accessible to the ordinary glass. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4719532]

DOI10.1063/1.4719532
Alternate JournalJ. Chem. Phys.