Potassium Cyanide Compound에 있어서 鐵 ion의 Mo¨ssbaur 효과

申榮男,李命夏 대구대학교 기초과학연구소 1987 基礎科學硏究 Vol.4 No.-

Isomer shift and quardrupole splitting of the ferric-and ferro-cyanide of potassium in accordance with temperature change in low temperature were studied by Mo∼ssbauer spectroscopy method. K₃Fe(CN)_(6) shows isomer shift and quardrupole, the other hand K₄Fe(CN)_(6)3H₂O shows only isomer shift. Two samples show that isomer shift is decreased by temperature decrease and quardrupole splitting is increased by temperature decrase. Accordingly selectron's contribution is increased by temperature decrease, a nucleus get to be more stable state. And it is showed that the nuclear state of K₄Fe(CN)_(6)3H₂O is more stabler than that of K₃Fe(CN)_(6).

CuO·V₂O_(5)·Fe₂O₃ 유리계의 Mossbauer 효과에 관한 연구

申榮男,李熙英 大邱大學校附設 基礎科學硏究所 1988 基礎科學硏究 Vol.5 No.-

The Mossbauer parameters, the valence state and the site of Fe ions in the xCuO·(1--x-y) V₂O_(5)·yFe₂O₃ glasses where x is O. 15, 0.20, 0.25 and 0.30 mole ratio and y is 0.12, 0.15 and 0.18 mole ratio have been studied by the Mossbauer spectroscopic method at room temperature. The samples are gotten by melting at 1200℃ for 3 hours and quenching in water and are revealed a glassy structure by the X-ray diffraction. The source of γ-ray is 5m Ci ^(57)o doped in rhodium. The observed pair of asymmetric lines suggest that Fe^(3+) ions exist both at octahedral and tetrahedral sites. There is no evidence of the presence of Fe^(2+)ions and Zeeman hyperfine spilitting. The addition of CuO increases the number of Fe^(3+) ions at the tetrahedral sites. The isomer shift increases with increasing CuO, which diminishes 4s electron density at both the octahedral and tetrahedral sites of iron nucleus. The quadrupole splitting decreases with increasing CuO, which changes the symmetry around the octahedral and tetrahedral sites of the iron ions. The isomer shift range of octahedral coordination is 0.261-0.290 mm/sec and that of tetrahedral coordination is 0.239-0.304 mm/sec. The quadrupole splitting for octahedral site ranges from 0.600 mm/sec to 0.749 mm/sec and that for tetrahedral sites ranges from 1.009 mm/sec to 1.274 mm/sec.

Sodium Nitroprusside 단결정의 Mossbauer Effect 연구

신영남,박성배,김재경 대구대학교 기초과학연구소 1999 基礎科學硏究 Vol.15 No.3

Sodium nitroprusside (Na2[Fe(CN)5NO]·2H2O) 단결성의 두께 변화에 대한 선폭의 증가를 측정하여 실험 선폭을 측정하였다. 또한 상온에서 sodium nitroprusside 단결정의 두께 증가에 대한 선폭의 증가를 조사하여 실험선폭을 측정하고, Dehye-Waller facters를 구하여 다른 실험결과와 비교하였다. 액체질소 온도에서 soium nitroprusside 단결정의 대칭성은 변하지 않고 Debye-Waller facters mean square displacement 값의 변화를 확인하고 또한 두께와 선폭치의 실험으로 측정한 Debye-Waller facter 값은 다른 실험값과 잘 일치하였으며 실험 선폭치는 자연 선폭에 대하여 약 16%에 상당하는 broadening을 확인 할 수 있었다.

비정질 Fe_(80)B_(20) 합금의 결정화

신영남,서동성,김재경,양재석 대구대학교 기초과학연구소 1995 基礎科學硏究 Vol.12 No.-

연자성 재료의 하나인 비정질 Fe_(80)B_(20) 합금을 단롤법으로 제작하여 주차열분석(Differential scanning calorimeter)실험을 통해 결정화 온도를 알아보고, 비정질 시료와 결정화된 시료를 X-선회절실험 및 Mo¨ssbauer 분광실험으로 생성된 결성상의 변화를 규명 분석하였다. DSC 실험을 통해서 얻은 결정화 시작온도 426℃, Peak온도 458℃, 종료온도 476℃임을 알았으며, 700℃에서 각각 1시간 동안 열처리를 하였다. 시료를 XRD로 분석한 결과 열처리 전에는 halo상의 비정질 상태임을 확인하였고, 열처리 후의 시료는 격자상수가 5.8Å인 α-Fe상과 격자상수가 a=8.63Å. c=4.29Å인 t-Fe_(3)B상이 나타남을 확인하였다. 결정화된 시료들의 Mo¨ssbauer spectrum은 4조의 6중선으로 연산하여 초미세자기장값과 상대면적값에 의해 각 시료의 Fe/B값으로부터 426℃, 458℃, 476℃에선 FeB상으로, 700℃에선 Fe_(2)B상과 Fe_(3)B상이 혼합되어 있다고 볼 수 있다. 한편 결정화된 시료들의 Mo¨ssbauer spectrum은 subspectra L1, L2, L3, L4, L5 및 L6의 6개의 6중선으로 fitting된 초미세자기장 α-Fe값은 333~339kOe, t-Fe_(3)B값은 220~295kOe, o-Fe_(3)B값은 230~283kOe 그리고 시료중 700℃에서 결정화된 L6의 초미세자기장값이 236kOe으로서 o-Fe_(3)B상과 t-Fe_(3)B상이 혼합되어져 있다고 볼 수 있다. 또한 열처리 온도가 증가 할수록 각 시료는 α-Fe상의 존재비가 증가하였고 t-Fe_(3)B상과 o-Fe_(3)B상이 공존하였으며, 700℃에서는 t-Fe_(2)B상이 존재함을 알았다. The crystallization of Fe_(30)&B_(23) amorphous alloy, prepared by rapid quenching from melt, was studied by differential s c a e calorimetry, X-ray djffraction and Mossbauer spectroscopy. Annealing condition was determined with the aid of DSC curves. From this measurements, this aUoy was annealed 1 hour at 426℃, 458℃ 476℃ and 700℃ in 5 × 10^(-6) torr. The lattice constants for the isochronally annealed Fe_(30)-B_(20) alloy were a-Fe(5.8A) and t-F~B(a=8.63A, c= 4.29A). The Mo¨ssbauer spectra of the Fe_(30)-B_(20) alloy consist of 6-sixlets absorption peaks. Hyperfine fields are obtained 333 - 339kOe, 2% - 295kOe, 252 - 262kOe, 220 - 225kOe, 272 - 283kOe and 230 - 236kOe. These phases are assumed to be crystalline α-Fe, t-Fe₃B, O-Fe₃B and t-Fe₂B.

Fe-Ge 화합물에 대한 Mossbauer효과

신영남,김재경,안범수 大邱大學校附設 基礎科學硏究所 1989 基礎科學硏究 Vol.6 No.-

Fe-Ge intermetalIic compounds were prepared as follows : the mixtures of Fe and Ge powder at the mole ratio of 1:1, 2:1 and 3:1 were melted at 1050℃ in the vaccum(10­³torr) for 50 hours and sintered at 650℃ for FeGe and at 850℃ for Fe₂Ge and Fe5Ge for 52 hours and then quenched in water. The crystal structures and internal magnetic fields of Fe-Ge intermetallic compounds were investigated by X-ray diffraction and Mossbauer spectroscopy. Mossbauer spectra of powdered samples were obtaind using a 57 Co/Rh source at room temprature. The values of internal magnetic fields of FeGe and Fe2Ge were 119.3 k0e and 238.3 k0e, respectively. And those of Fe2Ge were 127.2kOe, 185.1 k0e and 237.7kOe. The crystal structures of FeGe, Fe₂Ge and Fe₃Ge were hexagonal B35, B8₂, DO_(19), types, respetively.

Mössbauer 效果와 그 應用에 關한 硏究

신영남 대구대학교 (한사대학) 산업기술연구소 1982 産業技術硏究 Vol.2 No.1

Mössbauer effect is that γ-ray is radiated and absorbed from neuclear in the recoilless process. Mössbauer spectroscopy as a microscopic method has become important for elucidating the atomic arrangements and magnetic structures of the matterials. The magnitude of the hyperfine pattern is important with regard to the atomic structure, while the angular dependence of the hyperfine pattern gives information on the orientation of the spin. Mössbauer effect is applicated in various field of natural science. Specialy, its use is very important for physicists, chemists, biologists, mineralogists, metallurgists and engineers.

Alkali Borate 유리에 있어서 있어서 철이온의 Mo¨ssbauer 效果에 關한 硏究

申榮男,朴冠鎬,洪致裕 동국대학교 재료과학연구소 1982 材料科學硏究所 論文集 Vol.2 No.-

酸化鐵을 넣은 Alkali Borate 非晶質 유리를 만들어 Mo¨ssbauer Spectrum으로 Mo¨ssbauer parameters와 철 ion의 狀態에 대해서 硏究되었다. 試料의 成分은 X% A, (100-X)% B_2O_3, 4% Fe_2O_3로 하여 A는 K_2O, Na_2O, 및 K_2O이고, X=10,20 및 30을 취했다. 이 混合物을 잘 섞어 電氣爐에서 900℃ 溫度로 約 2時間동안 용융시켰다. I.S.와 Q.S.는 X가 增加함에 따라 減少함을 보였고, Li-Na-K의 原子半經에 따라 I.S.는 增加함을 보이나 Q.S.는 감소함을 보였다. 線幅은 X가 增加함에 따라, Li-Na-K 順序로 減少함을 보였다. Amorphous alkali borate glasses were prepared to contain 4 mole% of ferric oxide as impurity. Mo¨ssbauer parameters and the state of iron in alkali borate glasses were studied by Mo¨ssbauer spectra. X% A_2O, (100-X)% B_2O_3, 4% Fe_2O_3, where A=Li, Na or K and X=10, 20 or 30 are composed, were prepared. Mixtures were melted in air in furnace at 900℃ for two hours. Isomer shift and quadrupole splitting were decreased according to increasing of X component, and according to increasing of X component. Isomer shift was increased but quadrupole splitting was decreased. And the line width was decreased according to increasing of X component and Li-Na-K series.

Fe_(1.6)Ge의 金屬間 化合物의 構造에 관한 硏究

申榮男,朴成培,金相淵 大邱大學校附設 基礎科學硏究所 1986 基礎科學硏究 Vol.3 No.-

Constitution of Fe_(1.6)Ge system is disscussed by means of X-ray and Mossbauer effect. It has B8₂ type crystal structure and dissimilar atoms in two sublattice. Mossbauer effect show that the 2(a) site have larger I. S. , Q. S. and H. S. than 2(d) site. This show that the Fe^(2+) ion is occupied in 2(a) site but Fe^(3+) ion in 2(d) site. Negative Q. S. value of 2(d) site means that there is the noncollinear magnetic moment exist between two sublattice. Line width is so broad that we can image the many other site in the crystal.

Soda 유리에 있어서 鐵이온의 Mössbauer效果

신영남,박성배,김재경,오재환 대구대학교 산업기술연구소 1984 産業技術硏究 Vol.3 No.-

Mössbauer studies of a large number of glass samples prepared with alkali oxides in the region of glass formation are reported. In this study amorphous soda glasses were prepared with 4 mole% of ferric oxide as impurity. Mössbauer parameters and the valance state of iron in soda glasses were studied by Mössbauer spectra. X Na₂O·(100-X)B₂O₃·4Fe₂O₃ where X=10, 20 or 30 mole%, were prepared, and 10 A₂O·90 B₂O₃·4 Fe₂O₃ where A=Li, Na or K mole% were prepared for the study of the change with the ionic radii of alkali glasses. Mixtures were melted in air atmosphere in furnance at 900℃ for two hours. Mössbauer absorption measurements have been at room temperature. The γ-ray source is 3 mCi Co^(57) doped in Pd. In soda glasses isomer shift and quadrupole splitting were decreased according to increasing of X component and line width was increased. Isomer shift was increased, but quadrupole splitting and line width were decreased along the Li-Na-K series.

YBa₂(Cu_(1-x)Fe_(x))₃O_(9-y)계의 초전도성과 Mossbauer 효과

申榮男,金在慶,조현웅 大邱大學校附設 基礎科學硏究所 1990 基礎科學硏究 Vol.7 No.-

YBa₂(Cu_(1-x)Fe_(x))₃O_(9-y) superconductors are prepared and their physical characteristics are investigated by measuring the resistivity, X-ray diffraction pattens and Mossbauer spectra. At x=0.03, the crystal structure is transformed from orthorhombic to tetragonal system. Transition temperatures are not changed in the orthorhombic region, but linealy decreased with increasing x in the tetragonal region (80K at x=0.03 and 30K at x=0.1). The Mossbauer spectra are fitted to Lorentzian line shapes with two quadrupole doublets. Two main doublets and lattice parameters indicate that the valancy of Fe is +3. F2 site has typical square-pyramid coordination and F1 site has highly atypical (for Fe^(3+)) coorination of square-planar.