掺钕三硼酸铋晶体(Nd:BiB_3O_6)的光谱性质

采用顶部籽晶法, 生长了掺钕的新型非线性光学晶体Nd:BiB3O6, 测量了该晶体的折射率, 并拟合了晶体的折射率色散参数. 同时还测量了晶体的室温吸收谱, 并与0.2 mol/L的 NdCl3溶液的室温吸收谱进行了分析比较. 根据Judd-Ofelt理论, 拟合出晶体场唯象强度参数: Ω2 = 0.1776 × 10-20, Ω4 = 0.1282 × 10-20, Ω6 = 0.1357 × 10-20 cm2. 计算了各能级的辐射跃迁几率AJ,J', 荧光辐射寿命τ, 荧光分支比βJ'， 振子强度fJ,J'等. 根据这些光学参量, 讨论了该晶体的部分性能和应用前景.     

新型激光晶体α—Nd：Ba3Y（BO3）3光谱性能研究

研究了高温相掺钕硼酸钇钡α Nd∶Ba3Y(BO3)3(α NBYB)晶体的光谱特性。α NBYB晶体具有R3空间群结构。吸收光谱表明:该晶体在808nm左右有比较强的吸收峰,其对应于4I9 2→4F5 2,2H9 2的能级跃迁,半峰宽(FWHM)15nm,相应的吸收截面为1.56×10-20cm2,荧光光谱表明:4F3 2→4I11 2能级跃迁有很强的荧光发射,其发射波长为1.058μm,相应的荧光寿命为70μs,发射跃迁截面为1.82×10-19cm2,并用J O理论计算了该晶体的振子强度参数:Ω2=1.43×10-20,Ω4=2.08×10-20,Ω6=2.45×10-20cm2。     

Er~(3+)铋铅锶玻璃吸收光谱和上转换光谱

制备了新型掺Er3+铋铅锶玻璃,研究了玻璃的吸收光谱和上转换光谱性质,应用Judd-Ofelt理论计算了铋铅锶玻璃的3个强度参量Ωt(t=2,4,6),分别为Ω2=3·27×10-20cm2,Ω4=1.15×10-20cm2,Ω6=0.38×10-20cm2。计算了Er3+离子的振子强度、自发辐射跃迁几率、荧光分支比和辐射寿命等光谱参数。研究了上转换发光强度随泵浦激光功率的变化,上转换荧光525,546和657nm曲线的斜率分别为1·86,1·88和1·85,表明红、绿光发射均为双光子吸收过程。     

水热法合成YLiF4∶Er3+的上转换发光

用水热法合成了YLiF4∶Er3+,Er3+浓度变化范围为 0%～5%.在室温下,测试了所有样品在200～1200 nm间的吸收光谱.当 Er3+浓度为2%(Er-2样品)时,由吸收光谱计算得到的J-O参数为Ω2=1.05×10-20 cm2,Ω4=1.25×10-20 cm2和Ω6=1.35×10-20 cm2.在980 nm激发下,测试了所有样品的上转换发光光谱,发光强度随Er3+ 浓度增加而增长.当Er3+ 浓度小于1.5%,激发态吸收是主要的上转换发光机制.当Er3+ 浓度高于1.5%时,上转换机制包括激发态吸收和能量传递.在室温下,Er-2样品的能级2H11/2的寿命是205 μs,4S3/2的是205 μs,4F9/2是188 μs.根据实验数据和计算所得的跃迁几率,计算了4S3/2能级和4F9/2能级的量子效率,分别是27.9%和10.7%,表明两者都具有很高的量子效率.     

掺钕钒酸钆晶体的光谱特征

掺钕钒酸钆(Nd∶GdVO4)是性能优良的新型激光晶体,晶体在808nm处的吸收截面σabs=3.261×10-19cm2,在1064nm处的发射截面σem=9.283×10-20cm2,热导率与YAG相近,适合于LD泵浦,可用于研制全固化、低阈值、高效激光器。本文详细测定了其室温吸收光谱和荧光光谱,给出了Stark能级分裂数值。由于次近邻原子电负性较小,4I9 2→2P1 2谱线红移加大。晶体结构对超灵敏跃迁的影响大于非超灵敏跃迁。在0.91μm处有较强的荧光发射。     

掺钕三硼酸铋晶体(Nd:BiB3O6)的光谱性质

采用顶部籽晶法, 生长了掺钕的新型非线性光学晶体Nd:BiB₃O₆ , 测量了该晶体的折射率, 并拟合了晶体的折射率色散参数. 同时还测量了晶体的室温吸收谱, 并与0.2 mol/L的 NdCl₃溶液的室温吸收谱进行了分析比较. 根据Judd-Ofelt理论, 拟合出晶体场唯象强度参数: Ω ₂ = 0.1776 ´ 10^-20 , Ω ₄ = 0.1282 ´ 10^-20, Ω ₆ = 0.1357 ´ 10^-20cm². 计算了各能级的辐射跃迁几率A_J,J', 荧光辐射寿命τ , 荧光分支比β_J', 振子强度f_J,J'等. 根据这些光学参量, 讨论了该晶体的部分性能和应用前景.     

Nd:Na3La9O3(BO3)8晶体生长和性质研究

采用顶部籽晶法生长出掺杂浓度为3％的Nd：Na3La9O3（B03）8（Nd：NLBO）晶体。X射线粉末衍射图表明Nd：NLBO与NLBO的晶体结构相同，属于六方晶系。Nd：NLBO（3％）晶体的分凝系数为1．05。测试了晶体的吸收光谱，Nd：NLBO晶体在804nm有较强的吸收，吸收截面为3．2×10^20cm^2，半宽度为6．3nm。Nd：NLBO可能是一种潜在的自倍频晶体。     

钼硅酸电荷转移盐的合成、表征和晶体结构

以H4SiMo12O40·nH2O和六甲基磷酰三胺（[（CH3）2N]3PO，简写为HMPA）为原料，合成了分子组成为H4SiMo12O40·5HMPA·2H2O的光敏化合物。红外光谱研究表明，钼硅酸形成电荷转移盐后，其基本的Keggin骨架未变，但其特征振动峰发生了蓝移；光照变色后的漫反射电子光谱图上出现了Mo^Ⅴ→Mo^Ⅵ的IVCT吸收带，表明在光激发下发生了电子转移，ESR研究表明，电子转移处于单电子阶段；晶体结构分析表明，属三斜晶系，空间群P1，a=13.8490(10)×10^-1nm,b=13.9400(10)×10^-1nm,c=22.024(2)×10^-1nm,a=95.770(10)°,β=99.450(10)°,γ=91.510(10)°,V=4168.9(6)×10^-1nm,共收集21390个衍射点，对19037个独立衍射点做全矩阵最小二乘法计算，得可靠性因子R=0.046。     

新型掺铒铋酸盐玻璃上转换发光研究

制备了新型掺Er3 铋铅锶玻璃,研究了玻璃的吸收光谱和上转换光谱性质,应用Judd-Ofelt理论计算了铋铅锶玻璃的3个强度参量Ωt(t=2,4,6),分别为Ω2=3.27×10-20 cm2,Ω4=1.15×10-20cm2,Ω6=0.38×10-20 cm2.计算了Er3 离子的振子强度、自发辐射跃迁几率、荧光分支比和辐射寿命等光谱参数.研究了上转换发光强度随泵浦激光功率的变化,上转换荧光525,546和657 nm曲线的斜率分别为1.86,1.88和1.85,表明红、绿光发射均为双光子吸收过程.     

Etoposide的氧化还原反应: 脉冲辐解和激光光解研究

首次用脉冲辐解时间分辨方法研究了etoposide(VP16)在水溶液中与N~3^.,(SCN)~2^.^-和e~a~q^-之间发生的单电子氧化还原反应,测定了VP16的阴离子自由基、脱质子中性自由基的特征吸收谱;测得VP16与e~a~q^-,N~3^.,(SCN)~2^.^-的绝对反应速率常数分别为2.7×10^9,3.2×10^9和2.5×10^8dm^3.mol^-^1.s^-^1。研究表明,水溶液中的VP16可为248nm激光光电离,光电离的瞬态产物为阳离子自由基及脱质子中性自由基,并且测定了其酸碱电离的pK值。测得SO~4^.^-自由基单电子氧化VP16的反应速率常数为2.8×10^9dm^3.mol^-^1.s^-^1。     

Spectral Parameters of Nd^3＋ Ion in Nd^3＋：NaGd（MoO4）2 Crystal

1 INTRODUCTION Since the diode-laser pumped solid-state lasers were found in a wide variety of applications in the fields of military, industry, medical treatment and scientific researches due to the advantages of high stability, compactness, high efficiency and long life- time, the research on more efficient new materials with improved spectral properties for diode pumping has become more important. Molybdate crystals with general formula M’Re(MoO4)2 (M’ = Li, Na, K) have been repor…     

Spectral Parameters of Nd^3＋ Ion in Nd^3＋：KLu（WO4）2 Crystal

1 INTRODUCTION There has been increasing interest in the re-search of diode laser-pumped solid-state lasers in re-cent years because of the rapid development of highpower diode lasers. Nd:YAG and Nd:YVO crystalsare commercially available, but limited to low Nd3 (= 1 at.%) doping concentration and to narrow ab-sorption bands near the diode emission wavelengthof 808 nm. Therefore, it is necessary to explore moreefficient crystal materials for diode-pumped solid-state lasers. The alkali …     

Spectral Parameters of Nd^3＋ inthe Nd^3＋：GdMgB5O10 Crystal

1 INTRODUCTION With the development of diode-pumped solid-statelasers, the search of more efficient materials for diode-pumped solid-state lasers is becoming more and moreimportant. The good laser materials should have thefeatures of large absorption coefficient and large ab-sorption line widths, as well as large emission crosssection at the emission wavelength. In the past years,a number of Nd3 -doped crystals, such as Nd3 :YVO4 , Nd3 :YAG[2], Nd3 :KLW[3] and Nd3 : [1]YAP…     

Spectral properties of Nd-doped BiB_3O_6 crystal

Transparent Nd : BiB3O6 crystal has been grown by top-seeded method. The refraction indices of the crystal were measured and the parameters of chromatic dispersion were fitted. The room temperature absorption spectra of the crystal have been measured and compared with that of 0.2 mol/L NdCI3 solution. According to Judd-Ofelt (JO) theory, the spectral strength parameters Ω2 = 0.1776×10-20 cm2, Ω4 = 0.1282×10-20 cm2 and Ω6 = 0.1357×10-20 cm2 of Nd3+ ion were fitted. The radiative transition probabilities AJ,(?), oscillator strengths fJ,(?), radiative lifetime T and the branching ratio β(?) have all been calculated. Based on these parameters, the properties and application perspective are discussed.     

Spectral properties of Nd-doped BiB3O6 crystal

Transparent Nd: BiB₃O₆ crystal has been grown by top-seeded method. The refraction indices of the crystal were measured and the parameters of chromatic dispersion were fitted. The room temperature absorption spectra of the crystal have been measured and compared with that of 0.2 mol/L NdCl₃ solution. According to Judd-Ofelt (JO) theory, the spectral strength parameters Ω₂ = 0.1776×10^?20 cm², Ω₄ = 0.1282?10^?201 cm² and Ω₆ = 0.1357X10^-20 cm² of Nd³⁺ ion were fitted. The radiative transition probabilities A_J,J’, oscillator strengths f_J,J’, radiative lifetime rand the branching ratio β_J’ have all been calculated. Based on these parameters, the properties and application perspective are discussed.     

Growth and Spectral Characterization of Nd3+∶(Sr0.7Ca0.3)3Y(BO3)3 Crystal

A Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal with dimensions of 17×23 mm3 has been grown by the Czochralski method. The spectroscopic characterization of Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal was investigated. The polarized absorption cross-sections of Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal are 2.81×10-20 cm2 with full width at half maximum (FWHM) of 14 nm at 808 nm for σ-polarization and 2.04×10 -20 cm 2 with FWHM of 19 nm at 807 nm for σ-polarization, respectively. The polarized emission cross-sections of Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal are 12.2×10-20 cm2 at 1062 nm for the π-polarization and 13.6×10-20 cm2 at 1061 nm for the σ-polarization, respectively. After the Ca 2+ ion partly substitutes for Sr2+ ion in the Sr3Y(BO3)3 crystal to form the (Sr0.7Ca0.3)3Y(BO3)3 solid solution, it can improve the quantum efficiency of Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal. The quantum efficiency is 31.7%. These results may be regarded Nd3+ :(Sr0.7Ca0.3)3Y(BO3)3 crystal as a potential solid-state laser material.     

蝴蝶形原子簇化合物[MoOS3Cu2(PyPPh2)3]的制备、晶体结构 和非线性光学性质 研究

采用固相反应方法以[NH4]2[MoS2O2],CuI.Et4NBr和2-)二苯基膦)吡啶(PyPPh2)为原料制备了标题化合物。其结构用单晶分析法测定。测得化合物的分子式为MoOS3Cu2(PyPPh2)3],该晶体结构属三斜晶系,空间群为P1,所得晶胞参数为a=1.16736(4)nm,b=1.42254(5)nm,c=1.68034(6)nm,α=100.07°,β=103.2450(10)°,γ=105.0650(10)°,V=2.53991(15)nm^3,Z=2,Dc=1.504g·cm^-3,F(000)=1166,μ=13.57cm^-1.偏差因子R1=0.0590,wR2=0.1238。簇合物具有高度弯曲的蝴蝶状核,其中MoOS3^2-基团以三齿配体的形式与两个具有不同构型的Cu原子配位,氧原子不参加配位仅以端基形式存在。通过标题化合物在DMF中非线性光学性质的测定,表明其具有较好的非线性吸收和与以往不同的自散焦效应,算得其非线性吸收系数α2=4.4×10^-11m·W^-1,非线性折射系数n2=—8.225×10^-18m^2·W^-1;从而说明外围配体对非线性光学性质也具有大的影响作用。     

掺钕聚甲基丙烯酸甲酯的光学特性

Nd(DBM)3Phen-doped (DBM is dibenzoylmethane and Phen is phenanthroline) polymethyl methacrylate (PMMA) is prepared. Optical absorption, excitation and emission spectra were analyzed for Nd3+ in Nd(DBM)3Phen-doped PMMA. Using the Judd-Ofelt theory, the absorption spectrum was analyzed. The Judd-Ofelt(J-O) intensity parameters of Nd(DBM)3Phen-doped polymethyl methacrylate were calculated to be Ω2 = 20.97 × 10-20 cm2, Ω4 = 3.42 × 10-20 cm2, Ω6 = 2.90 × 10-20 cm2. The radiative lifetime (631 μs)of the excited 4F3/2 level is given. The stimulated emission cross-sections and the fluorescence branch ratios for the 4F3/2 →4 IJ/ transitions are also evaluated. Analysis reveals that Nd(DBM)3Phen-doped PMMA is promising for application in polymer optical fibers and planar waveguides.     

Growth and Characterization of Crystal Nd_(0.06)Y_(0.94)Sr_6Sc(BO_3)_6

<正>The crystal of Nd0.06Y0.94Sr6Sc(BO3)6 with the dimensions up to 35 mm × 28 mm × 13 mm was grown by a top-seeded solution growth method from Li6B4O9 flux. The grown crystal was characterized by X-ray powder diffraction. The optical absorption of the crystal shows that it has a strong absorption band at 8070 A, and the absorption coefficient is 2.17cm-1 with a FWHM of 41 A, which can match with the wavelength of the diode-laser (LD) and is suitable for the LD pumping. Based on the Judd-Ofelt theory, the three parameters of line oscillator strength Ω(λ) (λ = 2, 4 and 6) of the Nd3+ion in the crystal were calculated as follows: Ω2= 1.194 × 10-20, Ω4= 4.186 × 10-20 and Ω6 = 3.351 × 10-20cm2, which are relatively larger. The results indicate that the crystal Nd0.06Y0.94Sr6Sc(BO3)6 may be a kind of high-efficient laser material for diode-pumped.     

含吡唑啉酮酰肼类衍生物的合成与结构

报道了PMBP-NTH(NTH为烟酰肼)与PMBP-PAH(PAH为对甲氧基苯甲酰肼)的合成、表征和晶体结构分析,PMBP-NTH晶体属三斜晶系,具有P1空间群,a=0.9024(2)nm,b=1.0953(2)nm,c=1.1635(2)nm,α67.070(10)°,β=68.220(10)°,γ=84.770(10)°,V=0.9816(3)nm^3,Z=2,Dc=1.345g/cm^3,μ=0.090mm^-1,F(000)=416,R=0.0363,ωR=0.0870.PMBP-PAH属单斜晶系,具有P21/c空间群,a=1.2715(4)nm,b=0.91710(10)nm,c=1.8979(3)nm,β=106.890(10)°,V=2.1177(8)nm^3,Z=4,Dc=1.338g/cm^3,μ=0.090mm^-1,F(000)=896,R=0.0414,ωR=0.0972.这两个化合物在分子内都形成了大的共轭体系,由于分子间氢键力的作用,又使它们在晶体中以二聚体形式存在.