کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5403951 | 1392770 | 2007 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
High-resolution FTIR study of the para-terphenyl phase transition at high pressure
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
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چکیده انگلیسی
High-resolution infrared (IR) spectroscopy has been used to investigate the pressure-induced (0-11Â kbar) polymorphic phase transition of crystalline para-terphenyl at low temperature (25Â K). A number of doublet bands observed in low-pressure triclinic p-terphenyl were observed to coalesce in the high-pressure monoclinic phase. The coalescing of doublet bands was attributed to changes in factor group (Davydov) splittings associated with the transition from a low-pressure triclinic phase to a high-pressure monoclinic phase. The bands that 'disappear' also do not correlate with frequency changes associated with changes in molecular symmetry. Molecular dynamics (MD) simulations at low temperature (20Â K) yield a non-planar average molecular structure for the high-pressure monoclinic phase, in contrast to the high-temperature monoclinic phase. The MD simulations also reveal a broadening of the distribution of ring torsion angles near the triclinic-monoclinic phase transition pressure.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 127, Issue 1, November 2007, Pages 34-40
Journal: Journal of Luminescence - Volume 127, Issue 1, November 2007, Pages 34-40
نویسندگان
Bohdan Schatschneider, Eric L. Chronister,