SYNTHESES OF (C4H7OCH2C5H4)(2)LNCL (LN=ND, GD, DY, YB) AND CRYSTAL-STRUCTURE OF (C4H7OCH2C5H4)(2)DYCL

The reaction of lanthanide trichlorides with sodium tetrahydrofurfurylcyclopentadienyl in THF afforded bis(tetrahydrofurfurylcyclopentadienyl)lanthanide chloride complexes (C4H7OCH2C5H4),LnCl (Ln = Nd, Gd, Dy, Yb). All of the complexes were characterized

SYNTHESIS AND CRYSTAL-STRUCTURE OF ((C8H8)DY[MU-OCH2(CH2)2CH=CH2](THF))2

{(C8H8)Dy[mu-OCH2(CH2)2CH=CH2](THF)}2 was prepared by the reaction of (C8H8)DyCl(THF)n with CH2=CH(CH2)2CH2ONa in THF and characterized by spectroscopic, analytical and crystallographic methods. Its crystal structure shows that the complex is a dimer with

RVNb_2O_9(R=Y,Gd,La):Eu~(3+)(或Dy~(3+))的合成和光谱性质的研究

本文用R_2O_3(R=Y,Gd,La),V_2O_6,Nb_2O_5和高温固相反应法合成了复合钒铌酸盐RVMb_2O_3,并以此为基质研究了Eu~(3+)和Dy~(3+)在其中的光谱性质.实验表明,Eu~(3+)在这三个化合物中均处于偏离反演对称中心的格位上,Eu~(3+)的荧光强度的红/横比(R/O)和Dy~(3+)的黄/蓝比(Y/B)均随R~(3+)的电荷半径比的减小而下降.同时还研究了Bi~(3+)和温度对Dy~(3+)的发射强度的影响.

LUMINESCENCE OF BI(3+) AND THE ENERGY-TRANSFER FROM BI(3+) TO R(3+) (R=EU,DY,SM,TB) IN ALKALINE-EARTH BORATES

At room temperature, the Bi3+ ion shows broad band characters of its luminescence in Ca2B2O5, M3B2O6 ( M=Ca,Sr ) and SrB4O7. The maxima of the Bi3+ S-1(0)-->P-3(1) absorption bands are located in the range of 240-300nm, but the energy variation of the corresponding P-3(1)-->S-1(0) emissions is very large. The maxima of these emission bands change from 350nm in Ca3B2O6;Bi3+ to 586nm in SrB4O7:Bi3+. The Stokes shift of the Bi3+ luminescence increases from 6118 cm-1, in Ca2B2O5:Bi3+, to 24439 cm-1, in SrB4O7:Bi3+. The emission intensity of the Bi3+ luminescence increases with the decreasing Stokes shift. It has been found that in Ca2B2O5, the Bi3+ ion could transfer its excitation energy to the R3+ ions ( R=Eu, Dy, Sm, Tb ) , but in, Ca3B2O6 and Sr3B2O6, only Bi3+-->Eu3+ was observed. No energy transfer from Bi3+ to R3+ was detected in SrB4O7.

THE YELLOW-TO-BLUE INTENSITY RATION (Y/B) OF DY-3+ EMISSION

Various borates, vanadates, niobates, antimonates, titanates, zirconates and CaS doped with Dy3+ were prepared. Factors which have an effect on the yellow-to-blue intensity ratio (Y/B) of Dy3+ emission are reported. Y/B increases with decreasing Z/r or electronegativity of the next-neighbour element M in the complex oxides Dy-O-M. The greater the degree of covalency between Dy3+ and O2-, the greater Y/B is. When Dy3+ is located at a site with an inverse centre and high symmetry, Dy3+ displays no luminescence. It seems that Y/B of Dy3+ located at a site deviated from an inverse centre is greater than that of Dy3+ located at a site without an inverse centre. Y/B does not vary much with the variation in concentration of Dy3+ when Dy3+ is substituted for an element with the same valency, but it does depend on the concentration of Dy3+ when Dy3+ is substituted for an element with a different valency in the matrix, because defects are formed in this case.

YVO_4∶RE~(3+)(RE∶Pr、Sm、Tb、Es、Dy)晶体的研究

本文探讨了助熔剂法生长 YVO_4:RE~(3+)(RE:Pr,Sm,Tb,Er,Dy)晶体的工艺。讨论了助熔剂 V_2O_5,Pb_2P_2O_7和温度对晶体生长习性和缺陷的影响。测定了晶体的结构参数和光谱。Y_(0.9)Sm_(0.1)VO_4和 Y_(0.95)Dy_(0.05)VO_4晶体具有很好的光谱特性。

YP_xV_(1-x)O_4(0≤x≤1):Dy~(3+)的合成及其光谱性质的研究

本文报道了不同组成的YP_xV_(1-x)O_4(0≤x≤1):Dy~(3+)的合成和结构。YP_xV_(1-x)O_4(0≤x≤1)为四方晶系,晶胞参数随x的增大呈线性减小。基质的Stokes位移随x的增大逐渐变大,而激发光谱峰值则向短波方向移动。在YP_xV_(1-x)O_4:0.006Dy~(3+)体系中,x>0.4时出现的基质发射是由P0_4~(3-)引起的。基质及Dy~(3+)的发光效率和Dy~(3+)的发光强度的黄蓝比均与x有关。同时探讨了Bi~(3+)和温度对Dy~(3+)的发光强度的影响。

YV_(1-x)B_xO_(4-x):Eu~(3+)(或Dy~(3+),Bi~(3+))的合成及光谱性质的研究

本文报道了Eu~(3+)、D~(3+)在YV_(1-x)B_xO_(4-x)中的光谱性质。实验表明:B~(3+)取代V~(5+)时,可使基质和Dy~(3+)的发射强度及黄兰比下降,并使基质的吸收带短移。而B~(3+)取代Y~(3+)时,则可提高Dy~(3+)的黄兰比。同时我们还研究了Bi~(3+)和温度对YV_(0.69)B_(0.31)O_(3.69):Dy~(3+)中Dy~(3+)发射强度的影响。

新的稀土锂钒酸盐[Y_(0.5-x)Li_(1.5)VO_4:(Dy~(3+),Eu~(3+))_x]多波段发光

本文首次报道了新的稀土锂钒酸盐Y_(0.5-x)Li_(1.5)VO_4:(Dy~(3+),Eu~(3+))_x多晶粉末的制备,多波段发光和结构. 样品的制备是采用稀土氧化物(Y_2O_3Dy_2O_3和Eu_2O_3)纯度为99.99％与光谱纯的V_2O_5和Li_2CO_3按化学计量比混匀,在

稀土硼酸盐中影响Dy~(3+)发光的因素

60年代初对ABO_3型稀土硼酸盐的合成、结构和性质的研究已有报道。80年代侧重稀土和金属离子硼酸盐发光规律的研究。 Srivastava曾对GdBO_3中pr~(3+)的光谱及Gd~(3+)对Pr~(3+)的敏化、郭风瑜,李有谟

Ba_2RV_3O_(11)(R=Y,Gd,La):Eu~(3+)(或Dy~(3+),Bi~(3+))的合成及发光性能的研究

本文报导了Eu~(3+),Dy~(3+)在Ba_2RV_3O_(11)(R=Y,Gd,La)基质中的光谱性质、Bi~(3+)对Dy~(3+)发射强度的影响及温度对Dy~(3+)发射强度的猝灭情况.研究了被取代离子R~(3+)(R=Y,Gd,La)对基质电行迁移带、Eu~(3+)的红橙比、Dy~(3+)黄蓝比的影响,还给出了Dy~(3+)的浓度猝灭值.

INVESTIGATION ON THE LUMINESCENCE PROPERTIES OF DY-3+ AND EU-3+ IN ALKALINE-EARTH BORATES

In this paper, the yellow-to-blue intensity ratio of Dy3+ (Y/B) and the red-to-orange intensity ratio of Eu3+ (R/O) were studied in relation to the compositions and structures of alkaline-earth borates. The dependence of the energy of the Eu3+ charge-transfer band (CTB) and of the emission intensity of Dy3+ on the alkaline-earth ions and the boron content of the hosts is discussed.

硼酸盐玻璃中Gd~(3+)、Dy~(3+)、Bi~(3+)对Tb~(3+)发光性质的影响

本文研究了单掺和双掺(Tb~(3+)、Tb~(3+)+Gd~(3+)、Tb~(3+)+Dy~(3+)、Tb~(3+)+Bi~(3+)约四十余种不同成份的硼酸盐玻璃。探讨了玻璃成份对Tb~(3+)发光性质的影响和Gd~(3+)、Dy~(3+)、Bj~(3+)对Tb~(3+)的胜化作用。在B_2O_2-BaO-M_mO_n(M_mO_n=Li_2O、Na_2O、K_2O、MgO、CaO、SrO、Al_2O_3、La_2O_3和Bi_2O_3)玻璃体系中,当M_mO_n分别为MgO和Al_2O_3时,Tb~(3+)的发光强度最强;M_mO-n为Bi_2O_3时,Tb~(3+)的发光强度最弱。Tb~(3+)的特征发射峰分别随着碱金属、碱土金属和三价金属的离子半径增加而红移。Gd~(3+)、Dy~(3+)、Bi~(3+)对Tb~(3+)均有敏化作用。特别是Gd~(3+),使Tb~(3+)的发光强度增加1～3.8倍,其最佳敏化浓度,因基质玻璃成份而异。

LnAlO_3中Ce~(3+),Tb~(3+),Dy~(3+)的发光及Ce-Tb,Ce-Dy的敏化发光(Ln=La,Gd,Y)

本文采用BaF_2作为助熔剂和抑制剂经固相反应合成了一系列以LnAlO_3(Ln=La,Gd,Y)为基质的磷光体,系统地研究了LnAlO_3中Ce~(3+),Tb~(3+),Dy~(3+)的发光及Ce-Tb,Ce-Dy的敏化发光,发现随Ln的不同,LnAlO_3作为基质对激活剂的发光性质的影响也不同,本文得到一些规律性结果,并作了讨论。

Dy~(3+),Sm~(3+)和Ce~(3+)离子在M_3La_2(BO_3)_4(M=Ca,Sr,Ba)中光谱性质的研究

本文报导了Dy~(3+),Sm~(3+)和Ce~(3+)离子在M_3La_2(BO_3)_4(M=Ca,Sr,Ba)基质中的激发与发射光谱;研究了Dy~(3+)离子黄蓝发射的相强度随基质化合物的组成和结构的不同而呈现的变化规律;讨论了Sm~(3+)离子电荷迁移激发带的能量与基质中近邻阳离子的关系并分析了Sm~(3+)和Eu~(3+)离子4f电子构型对电荷迁移带能量的影响。本文还给出了Dy~(3+),Sm~(3+)和Ce~(3+)离子发光的浓度淬灭值。