کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9776492 | 1509486 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Ultraviolet photoemission and electron loss spectroscopy of oligothiophene films
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
بیومتریال
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Ultraviolet photoemission and electron loss spectroscopy of oligothiophene films Ultraviolet photoemission and electron loss spectroscopy of oligothiophene films](/preview/png/9776492.png)
چکیده انگلیسی
Ultraviolet photoelectron spectroscopy (UPS) has been used to study the evolution of the valence electronic states as a function of conjugation length for thiophene, bithiophene, terthiophene, and sexithiophene films deposited in-vacuum on gold substrates at 130 K. The peaks due to localized thiophene ring electronic states are found to be at ca. 8 eV below the vacuum level, regardless of the number (n) of thiophene rings in the chain. Peaks due to orbitals delocalized along the oligomer backbone progress to lower binding energies as the chain length increases from n = 2 to 6. Electron loss spectroscopy (ELS) has also been performed using an electron gun typically employed for Auger electron spectroscopy, and it is found that the lowest energy loss feature shifts to lower energy as conjugation length increases. The results obtained are in general agreement with theoretical and higher resolution experimental studies, and the thresholds of the lowest energy ELS peaks provide estimates of the bandgaps of the films. These results show that the combination of UPS and ELS provides a convenient means of evaluating the conjugation length of short-chain oligothiophenes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Synthetic Metals - Volume 150, Issue 3, 10 May 2005, Pages 259-264
Journal: Synthetic Metals - Volume 150, Issue 3, 10 May 2005, Pages 259-264
نویسندگان
A. Chandekar, J.E. Whitten,