Structure of High Temperature Phase α-Ba3Y（BO3）3 Crystal

1 INTRODUCTION To the present, the series of compounds M3Ln- (BO3)3 (M = Sr, Ba and Ln = La-Lu, Sc, Y) with space group P63cm or 3R have been reported[1～5]. Some of them exhibit interesting optical properties when doped into the active Cr3+ or Yb3+ ions as laser materials. For example, the Yb3+-doped Sr3Y- (BO3)3 crystal is a promising laser material for both tunable and femtosecond laser applications[6～8]. The Ba3Y(BO3)3 crystal melts congruently at 1256 ℃ and has a phase…     

Structure of Low Temperature Phase b-Ba_3Y(BO_3)_3 Crystal

1 INTRODUCTION Recently the series of compounds M3Ln(BO3)3 (M = Sr, Ba and Ln = LaLu, Sc, Y) with space group P63cm or -3R have been reported[1～5], and some of them exhibit interesting optical properties when doped with the active Cr3+ or Yb3+ ions as laser materials. For example, Yb3+-doped Sr3Y- (BO3)3 crystal is a promising laser material for both tunable and femtosecond laser applications[6～8]. The Ba3Y(BO3)3 crystal melts congruently at 1256 ℃ and has a phase transitio…     

Study on the Growth and Photorefractive Properties of In：Fe：Cu：LiNbO3 Crystals

Fe(0.2 mol%):Cu(0.04 mol%):LiNbO3 crystals with different doping concentration of In3+ (0, 1.0, 2.0, 3.0mol%) were grown by Czochralski method, and then oxidized and reduced. The infrared transmittance spectra of crystals were measured to investigate the location of doping ion and its threshold concentration. The photorefractive properties of the crystals were tested by two beam coupling experiment. The results showed that the threshold concentration of In ions is 2.0～ 3.0 mol% and In ions take the place of NbL 4i+ to form ( In L2i+) before reaching its threshold concentration, and then the location of normal Nb ions. In the (2.0 mol%):Fe:Cu:LiNbO3 crystal with the oxidation treatment having the highest diffraction efficiency (η = 45.8%), the photo-damage resistance threshold value R of In(3.0 mol%):Fe:Cu:LiNbO3 was 3.67×104 W/cm2 which was two orders of magnitude higher than that of Fe:Cu:LiNbO3 crystal (4.30×102 W/cm2). And the photo-damage resistance ability was enhanced by oxidized treatment. The In(2.0～3.0 mol%):Fe:Cu:LiNbO3 crystals with oxidized treatment have the best photorefractive properties.     

Holographic Storage Properties of In：Fe：Mn：LiNbO3 Crystals

In:Fe:Mn:LiNbO3(LN) crystals were grown in air atmosphere by Czochralski method with different concentration of In (0,1,2,3 mol%) in the melts,while the contents of Fe2O3 and MnO were 0.1 and 0.5 mol%,respectively. The location of doping ions was analyzed by Ultraviolet-visible absorption spectra and differential thermal analysis. The diffraction efficiency (η),writing time (τw) and erasure time (τe) of the crystals were measured by two-beam coupling experiment. The dynamic range and photorefractive sensitivity have also been calculated. The results showed that with the increase of In ions in the melt,the absorption edge of In:Fe:Mn:LN crystal shifts to the violet firstly and then makes the Einstein shift,the Curie temperature of crystal increases firstly and then decreases,the storage ratio speeds up,diffraction efficiency decreases,and dynamic range and photorefractive sensitivity increase. The mechanism of holographic storage properties of In:Fe: Mn:LN crystal with different doping concentration of In3+ was investigated,suggesting the In: Fe:Mn:LN crystals are excellent holographic storage materiel with better synthetical properties than Fe:Mn:LN crystals.     

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…     

Upconversion Properties of LiNbO_3 Single Crystals Co-doped with Ho and Yb

The IR-to-visible upconversion fluorescent crystals, Yb:Ho:LiNbO3, with a constant Ho3+ concentration (0.1 mol%) and different doping concentrations of Yb3+ (0.5, 1.5, 2.0, 2.5, 3.0 mol%) are synthesized by Czochralski method in air atmosphere. X-ray diffraction shows that the obtained crystal is a single phase of LiNbO3 and the rare-earth ions occupied the Li+ or Nb5+ sites instead of the interstitial sites. Under 980 nm excitation, green and red emission bands due to the Ho3+ (5S2, 5F4)/5I8 and Ho3+ 5F5/5I8 energy transitions are observed in these samples, respectively. Power dependence studies on these samples with different Yb3+ dopant concentrations indicate that the red and green emissions are based on a two-photon process. The intensities of the red and green upconversion fluorescence increase with Yb3+ ions of 0~2.0 mol% because of an increased Yb3+ sensitization, but decrease at higher concentrations owing to the back-energy transfer between the Yb3+ and Ho3+ ions.     

Growth and Spectral Properties of Yb^3＋-doped Ba3Gd（BO3）3 Crystal

Crystal of Yb3+-doped Ba3Gd(BO3)3 has been grown by the Czochralski method. The spectroscopic characterizations have been investigated at room temperature. The Yb3+:Ba3Gd(BO3)3 crystal exhibits broad absorption at 976nm with FWHM of 7nm and large overall spitting of 2F7/2 manifold (823cm-1). The absorption and emission cross sections are 5.09×10-21cm2 at 976nm and 0.97×10-21cm2 at 1040nm,respectively. The fluorescence lifetime is 2.84 ms.     

Thermal Properties of K（Y1-xYbx）（WO4）2（x=0.098,0.196,0.294） Crystal

Thermal properties of pure KY(WO4)2 and K(Y1-xYbx)(WO4)2(x=0.098,0.196,0.294) crystals were investigated.The specific heat and thermal diffusivity of crystals were calculated at a range of 50～300 ℃.The calculated result shows that the specific heat and thermal diffusivity of K(Y1-xYbx)(WO4)2(x=0.098,0.196,0.294) crystals were slightly affected by the Yb3+ concentration.The thermal expansion coefficient of K(Y0.804Yb0.196)(WO4)2 crystals along x,y and z axes were determined to be 13.51,4.474 and 16.60×10-6 K-1,respectively.These results suggest the K(Y1-xYbx)(WO4)2(x=0.098,0.196,0.294) crystal as a laser crystal of low-middle power.     

Researches on the Growth Habit and Optical Properties of Fe^3＋ Ion Doped KDP Crystal

During the process of KDP crystal growth,metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper,KDP crystals were grown from an aqueous solution doped with different concentration of Fe3+ dopant by traditional temperature-reduction method and "point-seed" rapid growth method. Furthermore,we examined the light scatter and measured the transmission of these KDP crystals. It is found that the dopant of Fe3+ ion can improve the stability of the KDP growth solution when its concentration is less than 30 ppm. The effects of Fe3+ ion on the growth habit and optical properties of KDP crystal are also obvious.     

PEG Assisted Hydrothermal Synthesis of β-Na YF_4:Yb~(3+),Er~(3+) Microrods for Upconversion Photoluminescence Display

β-Na YF4:Yb3+,Er3+ microrods with average length of 10 μm and diameter of 2.5 μm were synthesized through hydrothermal method. Based on the obtained microrods, transparent and flexible film with upconversion luminescence property was prepared through inorganic-organic composition method by using co-polymerization product of isobornylmethacrylate and urethane acrylate as the polymer substrate. The prepared film shows excellent optical transmission in the visible region with average transmission of 81.3% at high doping concentration(2 wt%) of β-Na YF4:Yb3+,Er3+ microrods. By directing and moving NIR laser beam toward the prepared film with high scanning speed, visible light is effectively emitted and various images are able to display.     

Synthesis and Structure of Ba3La2（BO3）4 Crystal

1 INTRODUCTION At present the researches on more efficient solid-state laser materials become more important for the rapid development of diode-laser pumped solid-state laser. More researches have been devoted to the double borate compounds RX3(BO3)4 (R = Y, La, Gd and X = Y, Al, Sc), some of which exhibit good chemical and physical properties[1～10]. The rare earth and alkali-halide double borates M3Ln2(BO3)4 (M = Ca, Sr, Ba and Ln = LaLu and Y) were reported in literatures[11…     

Hydrothermal synthesis and crystal structures of two novel acentric mixed alkaline earth metal berylloborates Sr3Be2B5O12(OH) and Ba3Be2B5O12(OH)

The synthesis and structure of the isostructural acentric compounds Sr(3)Be(2)B(5)O(12)(OH) (1) and Ba(3)Be(2)B(5)O(12)(OH) (2) are reported for the first time. These compounds crystallize in the space group R3m, and the unit cell parameters are a = 10.277(15) ? and c = 8.484(17) ? for 1 and a = 10.5615(15) ? and c = 8.8574(18) ? for 2. The structures consist of a network of [Be(2)B(4)O(12)(OH)] units interwoven with a network consisting of MO(9) polyhedra (M = Sr, Ba) and BO(3) triangles and exemplify how acentric building blocks such as [BO(3)](3-), [BO(4)](5-), and [BeO(4)](6-) can be especially suitable to build noncentrosymmetric long-range structures. Both networks are centered on the 3-fold rotation axis and present themselves in alternating fashion along [001]. Acentricity is imparted by the alignment of the polarities of BO(3) and BeO(4) environments. Infrared spectroscopy has been used to confirm the local geometries of B and Be, as well as the presence of hydroxide in the crystal structure. Another interesting feature of these compounds is the presence of disorder involving Be and B at the tetrahedral Be site. The degree of the disorder has been confirmed by observing a noticeable shortening of average Be-O bond distances.     

Structure of Non-stoichiometric Sr6Gd0.61Sc1.39（BO3）6 Crystal

1 INTRODUCTION With the increasing interest in diode-pumped solid state lasers, researches on more efficient new materials for diode pumping become more important. The double borates are a type of excellent laser gain media, for example, Nd3 -doped RAl…     

复合阴离子稀土穴醚配合物的分子和晶体结构研究

首次合成了稀土元素镱的异硫氰酸、硝酸复合阴离子穴醚(2,2,2)配合物H2Yb(NCS)~3(NO3)~2.H2O.(2,2,2)。测定了它的晶体结构及红外光谱, 发现Yb^3+没有进入穴醚空穴, 它通过H2O桥以氢键与穴醚的O原子结合。经研究认为, 分子中2个H^+结合在穴醚中2个N原子上。与Yb^3+配位的异硫氰酸根、硝酸根及分子形成八配位的三角十二面几何构型。晶体属单斜晶系, 空间群:P2~1/n。     

硼合多羟基醇希土配合物的合成与性质及其配位作用的研究

本文合成了硼合甘油希土和硼合葡萄糖希土二类共八个配合物。用化学分析、红外光谱、紫外光谱及热谱确定其组成为:RE(BO_2·C_3H_8O_3)_3·nCH_3OH和RE(BO_2·C_6H_(12)O_6)_3·3H_2O(RE=Nd、Gd、Y、Yb)。摩尔电导测定表明这两类化合物均为中性配合物。红外光谱显示出硼与多羟基醇之间以硼氧四面体形式结合。本文还通过电位滴定法讨论了希土与硼合多羟基醇之间的配位作用。     

Growth and Spectroscopic Properties of Nd3＋：Sr3Gd2（BO3）4 Crystal

<正>This paper reports the growth,X-ray diffraction and spectroscopy of Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal.A Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal with dimensions ofφ20×45 mm~3 has been grown by the Czochralski method.Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal belongs to the orthorhombic system,space group Pnma(D_(2h))with a=0.7401,b=1.604 and c=0.8755 nm.The absorption and emission spectra of Nd~(3+):Sr_3Gd_2(BO_3)_4 were investigated.The absorption cross sectionσ_a is 3.11×10~(-20)cm~2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm.The luminescence lifetimeτ_f is 51.7 us.The emission cross sectionσ_e at 1064 nm wavelength is 1.09×10~(-19)cm~2.     

MOLECULAR AND CRYSTAL STRUCTURE OF TETRAHYDROFURAN COORDINATED YTTERBIUM TRICHLORIDES YbCl_3(C_4H_8O)_3

<正> YbCl3(C4H8O)3, Mr = 495. 73, monoclinic, space group P21/c, a = 9.024(2), b=12.863(2), c=15. 762(7) A ,β=92. 21(2)°. V = 1828. 7(9) A3, Z = 4, DC=1. 801gcm-3, A(MoKa) = 0. 71073A, μ= 64. 44cm-1, F (000) = 964, R = 0. 075 for 2259 unique observed reflections. The Yb3+ ion is in a distorted octahedral coordination with three Cl ions and three O atoms from three tetrahydrofuran (THF) molecules. The average Yb -Cl distance is 2. 525A and Yb -O is 2. 303A.     

Structure and Properties of a New Rare-earth Borate LiSrY_2（BO_3）_3

The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell parameters at room temperature are as follows:a = 10.3345(9),c = 6.4049(11) ,V = 592.41(13) 3,Z = 3,Mr = 448.81,F(000) = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B(2) atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2(BO3)3 and photoluminescence properties of the Eu3+ doped LiSrY2(BO3)3 were also studied.     

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.     

R_3GeVO_9(R=Y,La)∶Eu~(3+)(或Dy~(3+))的合成及其发光性质

采用高温固相法合成了稀土复合钒锗酸盐R3GeVO9(R =Y ,La)体系 ,并以此为基质研究了Eu3+和Dy3+在其中的发光性质 ,以Eu3+为结构探针探讨了Eu3+在R3GeVO9(R =Y ,La)中的格位情况。同时 ,还研究了被取代离子R3+的Z/r对Eu3+的红橙比和Dy3+的黄蓝比的影响以及浓度、温度和Bi3+对它们发光强度的影响。