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1.
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…  相似文献   

2.
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…  相似文献   

3.
1 INTRODUCTION With the development of high power InGaAs laser diode (LD) as pump sources, the Yb3+-doped laser crystals have received much attention. Due to the simple energy level structure of the Yb3+ ions, the Yb3+-doped laser crystals have no concentration quenching, and have high quantum efficiency and low quantum defects even at high doping concentration of the Yb3+ ions[1, 2]. Therefore, the Yb3+-doped crystals are good candidates of media in the LD-pumped solid-state laser,…  相似文献   

4.
林奇生  程文旦 《结构化学》1998,17(4):245-248
The title compound Ba2 (BF4)4 crystallizes in the monoclinic spacegroup P21/n with crystallographic parameters: a = 8. 339 (3), b = 16. 530 (7), c =10. 212(4) A, V=1348. 7 A3, β= 106. 64(3)°, Z=4, Dc=3. 06 g/cm3, F(000)=1104, μ=5. 98 mm-1, (MoKa) =0. 71069, M= 621. 90. Least-squares refinementaffords the final residuals R=0. 0639 and Rw=0. 0676 for 2841 observed reflections (I>3(I)). The structure consists of columns of BF4 groups, which parallel to the b direction. All columns are linked together through Ba…F bonds, Both the two crystallographically different barium atoms are nine-coordinated by a distorted tri-capped prismof fluorine atoms from the nearest six BF4 tetrahedrons. There are two types of fluorineatoms, one connecting one barium atom and the other connecting two barium atoms.Each BF4 tetrahedron is connected to three barium atoms, so it (tetrahedron) can beviewed as unidentate ligand and bidentate ligand at the same time.  相似文献   

5.
涂朝阳  江爱栋 《结构化学》1989,8(3):215-219
<正> The crystal structure of Nd3+: Li6Y(BO3)3 is monoclinic, belonging to space group P21/c with the following cell constants:a =7. 157(5),b=16. 378(8),c = 6. 623(4)A.B=105. 32(5) ,Z=4,F =748. 8A3,Dc=2.747g/cm3. Mr (Li6Nd0.027 Y0.973(BO3)3) = 308. 47. The structure unit Li6Y(BO3)3 contains three B-O triangle planes,a distorted Y-O tetragonal prism,and five distorted Li-O trigonal bipyramids and one Li-O tetrahedron.  相似文献   

6.
1 INTRODUCTION With the development of diode-pumped solid-sta- te lasers, the research to find more efficient materials for these lasers is gaining more importance. The luminescent materials host LnMgB5O10 may become potential solid-state laser materials[1, 2]. Nd3 -doped GdMg(BO2)5 as a potential diode-pumped laser crystal has been grown in our lab and characterized by a very strong absorption at near 808 nm and intense emission. Although the previous work repor- ted LaMg(BO2)5 with…  相似文献   

7.
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。  相似文献   

8.
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.  相似文献   

9.
Nd^3 :GdAl3(BO3)4(NGAB) crystal with the size of 30 mm was grown from the solvent system of K2O-Gd2O3-MoO3-B2O3 by combining accelerated seed rotation technology with medium seeded solution growth (MSSG) method,and its crystal structure has been determined by X-ray powder diffraction.It crystallizes in the trigonal system,space group R32 with a=9.2743(2),c=7.2438(1)A,V=538A^3,Z=3and Dc=4.379g/cm^3,The absorption and emission spectra of NGAB in the function of σ and π polarizations at room temperature have been measured.UV generation tuneable in 378-382nm,green(531nm) generation and blue generation tuneable in 436-443 nm as well as red(669)nm generation by self-frequency changing were obtained with the oupput of 105, 119.5,445and 19μJ/pulse,respectively,when the crystal was pumped by a dye laser.  相似文献   

10.
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…  相似文献   

11.
The title compound was obtained by the flux method and its structure was determined. It crystallizes in monoclinic, space group P2/c with a = 11.0024(17), b = 9.2979(14), c = 14.500(2) A, β = 110.879(2)°, V = 1385.9(4) A^3, Z = 4, Mr= 908.38, F(000) = 1592, p = 19.601 mm^-1, Dc = 4.353 g/cm^3, the final R = 0.0481 and wR = 0.1257 for 2532 observed reflections with I 〉 2σ(I), The Rb3La3(BO3)4 structure can be viewed as a 3-dimensional scaffold-like framework constructed by La-O polyhedra and BO3 groups. Two Rb+ ions locate in a channel along the a direction and the rest one in a cavity.  相似文献   

12.
The title compound belongs to monoclinic,space group C2/c with a=5.2694(1),b=12.6659(4),c=19.4108(2) ,β=91.504(2)°,V=1295.06(5) 3,Z=4 and Dc=5.599 g/cm3. The structure of BaGd2(MoO4)4 contains a MoO4 tetrahedron,a distorted GdO8 polyhedron,and Ba2+ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices,thus forming a new Gd-Mo layer. Finally,the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 ,this structural characteristic will result in a cleavage along the (001) plane.  相似文献   

13.
卢绍芳  陈红兵 《结构化学》1995,14(4):261-263
CrystalStructureofCo(S_2CPh)_3LuShao-Fang;ChenHong-Bin;HuangXiao-Ying(FujianInstituteofResearchontheStructureofMatter,Academia...  相似文献   

14.
Reaction of anhydrous YbCl3 with 1 equiv, of LLi [L=p-ClPhNC(Me)CH(Me)N(C6H3-2,6-i-Pr2)] in THF at room temperature gave the β-diketiminate lanthanide dichloride LYbCl2(THF)2 (1) in good isolated yield. Similarly reaction of anhydrous YbCl3 with 1 equiv, of LLi, then with 1 equiv, of t-BuCpNa in THF yielded the expected mixed-ligand β-diketiminate ytterbium chloride (t-BuCp)YbL(μ-Cl)2Li(THF)2 (2). Both 1 and 2 were well characterized by elemental analysis, IR spectra, ^1H NMR spectra, and X-ray diffraction analysis.  相似文献   

15.
The title compound,a mixed(phthalocyaninato)(porphyrinato) yttrium double-decker complex 1,has been synthesized and structurally characterized by X-ray single-crystal diffraction method.Crystal data:monoclinic,space group C2/c,Z = 8,C79H52Cl10N12O4Y,Mr = 1676.74,a = 38.217(3),b = 18.9867(13),c = 26.200(3) ,β = 128.0190(10)°,V = 14977(2) 3,Dc = 1.487 g/cm3,μ(MoKα) = 1.196 mm-1,F(000) = 6808,R = 0.0745 and wR = 0.2208 for observed reflections with I > 2σ(I).X-ray analysis reveals that the coordination polyhedron adopts a slightly distorted square-antiprismatic structure around the metal center.Both phthalocyanine and porphyrin ligands are saucer-shaped,with the skew angle of the two ligand planes approximately 45°.  相似文献   

16.
1 INTRODUCTION In recent years, more and more attention has been paid to rare-earth borates due to their excellent pro- perties, such as YCa4O(BO3)3(YCOB)[1], YAl3(BO3)4 (YAB)[2] and La2CaB10O19[3] for nonlinear optical materials and self-frequency doubling materials as well as YBO3:Eu for red phosphor materials[4] and Li6M1-xCex(BO3)3 (M = Y, Gd) for neutron detec- tors[5]. In this work, we focus our research interest on LiY6O5(BO3)3 as hosts for VUV (vacuum ultraviolet) l…  相似文献   

17.
池利生  陈华阳 《结构化学》1998,17(4):297-301
1INTRODUCTIONRareearthborosilicateshaverarelybeenreportedinthepastdecade.LnBMO5(M=Ge,Si)(l,z,31exhibitsthestillwellitestructureonlyforlargerlanthanide,initsstructure,twoBO'tetrahedraandoneSiO'tetrahedronareconnectedbycorner-sharedeachothertoformsix-memberringthatconstructinfinitehelicalchainsparal-lelto3lscrewaxis-Serhanetal(43synthesizedNd,BM2O,,(M=Si Ge)whosestructurecontainstri-coordinatedboronatoms.Recently,wehavesynthesizedSm3BSi2O1,andEu,BSi,O,,t"6),herewerffportthesynthes…  相似文献   

18.
Growth and Characterization of γ—Nd^3+:LaSc3(BO3)4Crystal   总被引:1,自引:0,他引:1  
林洲斌  王国富 《结构化学》2001,20(4):256-258
INTRODUCTIONLaser-diode(LD) pumped solid-state lasers have a 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 lifetime, and this area has become one of the hot points in the laser field. As a result, research on new materials with improved spectral properties for diode pumping is of increasing interest again. A new high efficient diode-laser-pumped solid-s…  相似文献   

19.
Solid—state Synthesis at Low—heating Temperature and Crystal Structure   总被引:2,自引:0,他引:2  
汤卡罗  倪海洪 《结构化学》1994,13(4):300-303
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20.
李媛  金声 《结构化学》1999,18(5):331-334
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