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NaCeF(SO_(4))_(2):新型氟化铈硫酸盐合成结构及其粉末非线性光学性能研究
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作者 陆心宜 王睿曦 +2 位作者 李梦月 吴立明 陈玲 《人工晶体学报》 北大核心 2025年第10期1772-1779,共8页
本文采用水热法,合成了新型二硫酸氟化铈(Ⅳ)钠(NaCeF(SO_(4))_(2))。该化合物结晶于非中心对称的P212121空间群(No.19),晶胞参数为a=8.2330(2)A,b=8.5910(2)A,c=9.2611(2)A,α=β=γ=90°,V=655.03(3)A^(3),Z=4。其晶体结构以三维... 本文采用水热法,合成了新型二硫酸氟化铈(Ⅳ)钠(NaCeF(SO_(4))_(2))。该化合物结晶于非中心对称的P212121空间群(No.19),晶胞参数为a=8.2330(2)A,b=8.5910(2)A,c=9.2611(2)A,α=β=γ=90°,V=655.03(3)A^(3),Z=4。其晶体结构以三维网格骨架为特征,该骨架由[CeO_(7)F_(2)]多面体链和[NaO_(8)]多面体链交织而成;链间空隙处填充以孤立的(SO_(4))四面体。该材料实验带隙约为2.70 eV,表现出良好非线性光学性能(1064 nm激光下,倍频强度约为KDP的2倍)。相较于中心对称母体Ce(SO_(4))_(2),氟原子作为第二配体诱导结构畸变,促使非中心对称结构NaCeF(SO_(4))_(2)的形成。第一性原理计算研究表明该化合物的带隙主要由Ce-4f、O-2p、S-3p及F-2p所构成的晶体轨道决定;其二阶非线性光学性质主要由[CeO_(7)F_(2)]多面体决定,(SO_(4))四面体仅起次要作用,二阶非线性光学系数(d_(14)=d_(25)=d_(36))计算值为-2.672 pm/V。 展开更多
关键词 非线性光学材料 氟化铈硫酸盐 晶体结构 第一性原理 NaCeF(SO_(4))_(2)
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Electrochemical studies on cerium(Ⅲ) in molten fluoride mixtures 被引量:4
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作者 VIRGIL CONSTANTIN ANA-MARIA POPESCU MIRCEA OLTEANU 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第3期428-434,共7页
This study aims to determine the principal electrochemical characteristics of the electrodeposition of cerium metal from molten fluoride systems.The cathodic process of Ce3+ ions in LiF-NaF and LiF-NaF-CaF2 molten sal... This study aims to determine the principal electrochemical characteristics of the electrodeposition of cerium metal from molten fluoride systems.The cathodic process of Ce3+ ions in LiF-NaF and LiF-NaF-CaF2 molten salts was studied using electrochemical techniques as steady state and cyclic voltammetry methods.The decomposition potential(Ed) and the overvoltage(η) were determined for NaCeF4 using current-potential curves under galvanostatic conditions.The Ed was found to be 2.025 V in LiF-NaF and 2.045 V in... 展开更多
关键词 CERIUM molten salts LANTHANIDES nacef4 ELECTROLYSIS cyclic voltammetry
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Structure and heat capacity of the NaCeF_4 compound
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作者 Virgil Constantin Ana-Maria Popescu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第9期911-915,共5页
This work continued our general research program on obtaining metallic cerium by electrodeposition from NaCeF4 dis-solved in different molten fluorides. The structure of NaCeF4 (cubic or hexagonal depending on the wa... This work continued our general research program on obtaining metallic cerium by electrodeposition from NaCeF4 dis-solved in different molten fluorides. The structure of NaCeF4 (cubic or hexagonal depending on the way of preparation) was estab-lished by DTA analysis, IR spectra and X-ray diffraction. The heat capacity (Cp) of NaCeF4 was measured by differential scanning calorimetry in the temperature range of 300-1093 K using the“step-method”. The Cp was fitted by an equation with a satisfactory re-sult. Heat capacity was compared with that calculated from the Neumann-Kopp rule (NKR) and the deviations observed were consis-tent with the stability of the NaCeF4 compound. 展开更多
关键词 cerium compounds STRUCTURE heat capacity nacef4 rare earths
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NaCeF_4:Tb^(3+)纳米棒的溶剂热合成及光学性质研究
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作者 曲雪松 李志欣 《科技视界》 2017年第26期8-9,26,共3页
本文采用溶剂热法合成了单分散的六角相NaCeF_4:Tb^(3+)纳米棒荧光材料并对其结构、形貌、尺寸及光学性质进行了表征。研究结果表明,氟化铵的用量对产物的结构、形貌和尺寸起着非常重要的作用,F-的选择性吸附是获得不同长径比产物的主... 本文采用溶剂热法合成了单分散的六角相NaCeF_4:Tb^(3+)纳米棒荧光材料并对其结构、形貌、尺寸及光学性质进行了表征。研究结果表明,氟化铵的用量对产物的结构、形貌和尺寸起着非常重要的作用,F-的选择性吸附是获得不同长径比产物的主要原因。同时晶体的各向异性生长显著改善了Ce^(3+)周围的晶场环境,影响了Ce^(3+)向Tb^(3+)的能量传递路径。 展开更多
关键词 nacef4:Tb^3+ 溶剂热 各向异性
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