Yttrium Iron Garnet Y_(3-x)Fe_(5+x)O_(12)(x=O.O, O.18, 0.33, 0.60)계의 Mossbauer 분광학적 연구 = Mossbauer Study of Yttrium Iron Garnet Y_(3-x)Fe_(5+x)O_(12)(x=O.O, O.18, 0.33, 0.60) System

다국어 초록 (Multilingual Abstract)

The yttrium iron garnet system Y_(3-x)Fe_(5+x)O_(12)(x=0.0, 0.18, 0.33, 0.60) has been investigated by means of the X-ray diffraction and Ma¨ssbauer spectroscopy.
The structure of this system has been found to be a garnet structure from the result of X-ray diffraction analysis. The lattice constants slowly decrease(12.372~12.360Å) with increasing x (0.0~0.60)
The Mo¨ssbauer spectrum for x=0.0 at room temperature consists of two Zeeman sextets, one due to the Fe^(3+) on octahedral a-site and the other due to the Fe^(3+) on tetrahedral d-site, respectively. However the spectrum shows four Zeeman sextets in the range between x=0.18 and 0.60 due to two octahedral a-, a'-site and two tetrahedral d-, d'-site with different hyperfine parameters(isomer shift, quadrupole splitting, magnetic hyperfine field).

목차 (Table of Contents)

• 목차 = 1
• ABSTRACT = 2
• 제1장 서론 = 3
• 제2장 이론적 배경 = 5
• 2-1. Mo¨ssbauer 효과 = 5
• 2-2. 초미세 상호작용(hyperfine interaction) = 6
• 2-2-1. 전기 홀극 상호작용과 이성질체 이동 = 6
• 2-2-2. 전기 4중극자 상호작용과 4중극자 분열 = 11
• 2-2-3. 자기 2중극자 상호작용과 핵 Zeeman 효과 = 14
• 2-2-4. 전기 4중극자 상호작용과 자기 2중극자 상호작용의 혼합 = 16
• 2-3. Mo¨ssbauer 스펙트럼에 나타나는 여러가지 효과 = 18
• 2-4. Garnet 구조 = 21
• 제3장 실험 = 23
• 3-1. 시료제조 = 23
• 3-2. X-ray 회절실험 = 23
• 3-3. Mo¨ssbauer 분광실험 = 24
• 3-4. 고온실험 = 25
• 제4장 결과 및 논의 = 27
• 4-1. 결정구조 = 27
• 4-2. Mo¨ssbauer spctrum = 30
• 제5장 결론 = 40
• 참고문헌 = 41