α-Fe2O3原子結構的複繞射研究

Study of atomic structure of α-Fe2O3 using multiple X-ray diffraction

賴彥仲(Yen-Chung Lai)

指導教授 ： 杜昭宏

淡江大學/理學院/物理學系碩士班/碩士(2009年)

https://doi.org/10.6846/TKU.2009.01161

摘要

在這篇論文中我們使用X光複繞射來研究赤鐵礦α-Fe2O3的三光相位與電子結構的關聯性。在此次實驗中，我們沿著鐵的K-edge逐漸增加能量，觀察三光繞射峰的變化，發現到三光繞射峰的相位會慢慢的改變，在pre-edge(E=7.113 keV)與鐵的K-edge(E=7.123 keV)兩個能量的位置各有一次相位180度的轉變，並且在其他的三光繞射峰也同樣有兩次相位的轉換。因為相位與結構因子有很大的關係，所以我們認為關於兩次相位的轉變與α-Fe2O3的電子結構有很大的關聯。

關鍵字

複繞射 ； 相位

並列摘要

We report the x-ray multiple-wave diffraction on a high quality single crystal hematite α-Fe2O3. Multiple-wave diffraction is a very useful method to study the phase problem of material structure. In this experiment, we observed the pre-edge (E=7115 eV) feature near the Fe K-edge (E=7123 eV) from the absorption spectrum of α-Fe2O3. Using multiple-diffraction and analyzing the interference effect from the three-beam diffraction case as a function of incident x-ray energy, we observed that the phase of the structure factor changes at the pre-edge and K-edge, respectively. This double-jump of the phase suggests that hematite α-Fe2O3 has a complicated electronic structure.

並列關鍵字

Multiple-wave diffraction ； Phase

參考文獻

[1] 國家同步輻射研究中心 (National Synchrotron Radiation Research Center)，http://www.nsrrc.org.tw

[5] Chang, S.L.“Multiple diffraction of X-ray in crystals” Springer-Verlag (1984).

[6] Shih-Lin Chang, Chin. Journal of Physics 23, 181-192 (1985)

[10] G. Zschornack “Handbook of X-Ray Data” Springer (2007)

[11] B.D. CULLITY “ELEMENTS OF X-RAY DIFFRACTION” first edition. (1965)