The investigations on the electronic states of crystals of alkali halides, including energy band structures for perfect crystals and descriptions of different kind colour centers, are important subjects in solid state...The investigations on the electronic states of crystals of alkali halides, including energy band structures for perfect crystals and descriptions of different kind colour centers, are important subjects in solid state physics. Especially since the seventies, with the rapid development of colour center laser, investigations in this field arouse more and more interest of researchers.展开更多
The electron spin resonance, transmission and reflection spectra showed that a steadily electron-type paramagnetic complex color point defect Fn center is produced by 60Co γ-ray strong dose irradiation in a single cr...The electron spin resonance, transmission and reflection spectra showed that a steadily electron-type paramagnetic complex color point defect Fn center is produced by 60Co γ-ray strong dose irradiation in a single crystal LiF. The γ-ray irradiation dose is too large to recognize any character peak of F2, F2, F2, and F3 centers in the transmission and reflection spectra of the single crystal. LiF: Fn is opaque when wavelength is shorter than about 750nm and has not refiection when wavelength is shorter than about 800nm. The Fn center has a wide ESR peak with ΔBpp of 8 millitesla and the effect g-factor is 1.998±0.002.展开更多
Herein, the present paper were attempted to identify ions in LiF-DyF_3 melts according to the law of decreasing primary crystallization temperature and model analysis. Specifically.the primary crystallization temperat...Herein, the present paper were attempted to identify ions in LiF-DyF_3 melts according to the law of decreasing primary crystallization temperature and model analysis. Specifically.the primary crystallization temperatures of LiF-DyF_3 and LiF-DyF_3-Dy_2O_3 melts with various DyF_3 and Dy_2O_3 contents were determined by differential scanning calorimetry(DSC), and reactions occurring in the above melts were investigated using ideal dilute solution(Temkin and Flood) models. Moreover, crystal phases produced by rapid solidification of LiF-DyF_3, LiF-Dy_2O_3, DyF_3-Dy_2O_3, and LiF-DyF_3-Dy_2O_3 melts were identified by X-ray diffraction(XRD) analysis. The primary crystallization temperature of LiF-DyF_3 melts exhibits an approximately linear decrease with increasing molar fraction of DyF_3, and the general formula of complex ions in these melts is expressed as DyF_x^((3-x)),e.g., DyF_4^-. Finally, we investigated the dissolution of Dy_2O_3 in LiF-DyF_3 melts, showing that it was chemical in nature and afforded Dy_(1+x)O_(3x)F_(3-3x) and DyOF.展开更多
文摘The investigations on the electronic states of crystals of alkali halides, including energy band structures for perfect crystals and descriptions of different kind colour centers, are important subjects in solid state physics. Especially since the seventies, with the rapid development of colour center laser, investigations in this field arouse more and more interest of researchers.
文摘The electron spin resonance, transmission and reflection spectra showed that a steadily electron-type paramagnetic complex color point defect Fn center is produced by 60Co γ-ray strong dose irradiation in a single crystal LiF. The γ-ray irradiation dose is too large to recognize any character peak of F2, F2, F2, and F3 centers in the transmission and reflection spectra of the single crystal. LiF: Fn is opaque when wavelength is shorter than about 750nm and has not refiection when wavelength is shorter than about 800nm. The Fn center has a wide ESR peak with ΔBpp of 8 millitesla and the effect g-factor is 1.998±0.002.
基金Project supported by the National Natural Science Foundation of China(5167041092,51564015)Natural Science Foundation of Jiangxi Province(20161BAB206142)Outstanding Doctoral Dissertation Project Fund of JXUST(YB2017007)
文摘Herein, the present paper were attempted to identify ions in LiF-DyF_3 melts according to the law of decreasing primary crystallization temperature and model analysis. Specifically.the primary crystallization temperatures of LiF-DyF_3 and LiF-DyF_3-Dy_2O_3 melts with various DyF_3 and Dy_2O_3 contents were determined by differential scanning calorimetry(DSC), and reactions occurring in the above melts were investigated using ideal dilute solution(Temkin and Flood) models. Moreover, crystal phases produced by rapid solidification of LiF-DyF_3, LiF-Dy_2O_3, DyF_3-Dy_2O_3, and LiF-DyF_3-Dy_2O_3 melts were identified by X-ray diffraction(XRD) analysis. The primary crystallization temperature of LiF-DyF_3 melts exhibits an approximately linear decrease with increasing molar fraction of DyF_3, and the general formula of complex ions in these melts is expressed as DyF_x^((3-x)),e.g., DyF_4^-. Finally, we investigated the dissolution of Dy_2O_3 in LiF-DyF_3 melts, showing that it was chemical in nature and afforded Dy_(1+x)O_(3x)F_(3-3x) and DyOF.