Thermal tunable one-dimensional photonic crystals containing phase change material

To obtain the adjustable photonic crystals (PCs), we numerically investigate one-dimensional (1D) PCs with alternating VO2 and SiO2 layers through transfer matrix method. The dispersion relation agrees well with the transmittance obtained by the finite element calculation. Tunable band gaps are achieved with the thermal stimuli of VO2, which has two crystal structures. The monoclinic crystal structure VO2 (R) at low temperature exhibits insulating property, and the high temperature square rutile structure VO2 (M) presents metal state. Concretely, the bandwidth is getting narrower and red shift occurs with the higher temperature in VO2 (R)/SiO2 PCs structure. Based on the phase change characteristics of VO2, we can flexibly adjust the original structure as VO2 (R)/VO2 (M)/SiO2. By increasing the phase ratio of VO2 (R) to VO2 (M), the band gap width gradually becomes wider and blue shift occurs. The discrete layers of gradient composites on the dispersion of 1D PCs are also investigated, which enhances the feasibility in practical operation. Thus, our proposed thermal modulation PCs structure paves a new way to realize thermal tunable optical filters and sensors.

Investigation of Photonic Band Gap in Si-Based One-Dimensional Photonic Crystal

A one-dimensional silicon based photonic crystal with nonlinear defect layers is examined. The linear and nonlinear optical properties are analyzed. The transmission spectrum was obtained by applying the optical transfer matrix formalism to the photonic crystal. The various transmittance peaks obtained with the defect layers are investigated. The nature of the transmittance peak is analyzed with the number of defect layers.

Synthesis and Crystal Structure of 1-(4-Fluorophenyl)-2-hexylthiobenzo[4,5]-furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H)-one

The crystal structure of the title compound 1-（4-fluorophenyl） -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5（1H） -one（C23H21FN4O2S,Mr = 436.5） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854（3） ,b = 17.2678（4） ,c = 18.1828（5）A,β = 99.364（2） °,V = 4332.58（18） A^3,Z = 4,Dc = 1.338,F（000） =1824,μ = 0.185 mm^-1,MoKa radiation（λ = 0.71073） ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I 〉 2σ（I） . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5（1H） -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions.

Synthesis and Crystal Structure of 2-Ethoxy-3-n-butyl-benzofuro [2,3-d]pyrimidin-4(3H)-one

The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4（3H）-one （C16H18N2O3, Mr = 286.32） has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167（14）, b = 13.113（1）, c = 8.378（1） A, β = 98.992（2）^o, V = 1488.4（3） A^3, Z = 4, Dc = 1.278, F（000） = 608, μ = 0.089 mm^-1, MoKa radiation （2 = 0.71073）, R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.

Synthesis and Crystal Structure of a Cu(Ⅱ) Complex with Reduced Schiff-base N-(2-Hydroxybenzyl)-D,L-alanine and 4,4'-Bipyridine

A new complex [Cu2（sala）2（H20）2（4,4＇-bipy）]＇H20 （sala = N-（2-hydroxybenzyl）- D,L-alaninate, 4,4＇-bipy = 4,4＇-bipyridine） has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. The complex crystallizes in monoclinic system, space group C2/c with a = 42.44（3）, b = 10.416（8）, c = 15.487（13） ./k, fl = 97.455（14）°, C30H36Cu2N4O9, Mr = 723.71, V = 6789（9） A3, Dc = 1.416 g/cm3, Z = 8, F（000） = 2992, μ（MoKa） = 1.308 mm-1, R = 0.0493 and wR = 0.1004 for 4878 observed reflections （I 〉 2σ（I））. Structural analysis shows that each copper（II） atom displays a distorted square-based pyramidal coordination geometry with two oxygen atoms and one nitrogen atom from one N-（2-hydroxybenzyl）-D,L-alaninate, one nitrogen atom from 4,4＇-bipyridine ligand and one water molecule. 4,4＇-Bipyridine ligand bridges two Cu（II） ions to form a dinuclear compound. The molecular structure is extended into a one-dimensional wavy chain through hydrogen bonds. These 1D chains are further expanded into 2D networks through hydrogen bonds.

Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate

The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.

Synthesis and Crystal Structure of 2-(3,3'-Bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(Dithieno[2,3-b:3',2' -d]thiophen-2,5-yl)dibenzothiazole (DTTDB)

The title compounds, 2-（3,3＇-bithiophen-2,2＇-yl）dibenzothiazole （BTDB） and 2-（dithieno[2,3-b：3＇,2＇-d]thiophen-2,5-yl）dibenzothiazole （DTTDB）, have been synthesized and characterized by FT-IR, NMR, MS, HRMS and X-ray single-crystal diffraction. The crystal of BTDB crystallizes in triclinic, space group P1 with a = 9.2207（17）, b = 10.453（2）, c = 10.969（2） A, V= 981.2（3） A3 and Z = 2. Crystal data of DTTDB： orthorhombic system, space group Pbcn with a = 4.5290（8）, b = 13.576（3）, c = 32.033（6） A, V= 1969.6（6） A3 and Z = 4.

Synthesis and Crystal Structure of 2-(4’-Methylphenoxy)-5,8,9-trimethyl-3-phenyl Thieno[3′,2′:5,6]pyrido[4,3-d]pyrimidin-4-(3H)-one Hydrochloride

The title compound 2-（4＇-methylphenoxy）-5,8,9-trimethyl-3-phenyl thieno[3＇,2＇：5,6] pyrido[4,3-d]pyrimidin-4（3H）-one hydrochloride （C26H23Cl4N3O2S, Mr = 583.33） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.8442（ 11 ）, b = 11.5131 （8）, c = 17.2010（13） A, β = 113.7250（10）°, V = 2691.3（3） ,A^3, Z = 4, Dc = 1.440 g/cm^3, S = 1.094,μ = 0.547 mm^-1, F（000） = 1200, the final R = 0.0571 and wR = 0.1458. X-ray analysis reveals that the title compound combines with a molecule of dichloromethane by an intramolecular hydrogen bond. The thienopyridine ring is almost coplanar, and the dihedral angle between the thiophene plane and the pyridine plane is 0.6°.

Hydrothermal Synthesis,Crystal Structure and Luminescent Properties of an Organically Templated 2-D Uranyl Sulfate

An organically templated 2-D uranyl sulfate, {（C2H8N）[（UO2）Cl（SO4）（H2O）] }n 1, has been hydrothermally synthesized. The crystal and molecular structures have been determined by X-ray crystallography method and spectral techniques. 1 belongs to monoclinic, space group P21/c with a = 8.3545（17）, b = 10.550（2）, c = 12.370（3）A, β = 102.64（3）°, V = 1063.9（4）A3, Mr = 464.64, De= 2.901 g/cm^3, F（000） = 836,μ = 15.710 mm^-1, Z= 4, the final R = 0.0286 and wR = 0.0685 for 10164 observed reflections with Ⅰ 〉 2σ（Ⅰ）. 1 presents a two-dimensional layer-like structure constructed from infinite anionic [（UO2）Cl（H2O）（SO4）]^- layers with [C2H8N]^＋ cations balancing the charge and a number of intermoleeular hydrogen bonds （C-H…O and O-H…Cl） existing in the solid state. The fluorescence properties of 1 have also been discussed.

Synthesis and Crystal Structure of 7-Amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)-2,4-dioxo-1H-pyrano[2,3-d]pyrimidine-6-carbonitrile DMF Solvate

The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-（2-nitrophenyl）- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 （C19H20N6O6, Mr = 428.41） was synthesized and crystallized. The crystal belongs to the monoclinic system, space group P2 1/c with a = 11.383（2）, b = 13.372（2）, c = 13.673（2）A, β = 97.380（4）°, Z = 4, V = 2063.8（6）A^3, Dc = 1.379 g/cm^3,μ（MoKα） = 0.105 mm^-1, F（000） = 896, the final R = 0.0738 and wR = 0.1647 for 2964 observed reflections （I〉 2σ（I））. X-ray analysis reveals that the new pyran ring is coplanar, which is obviously different from those of other similar compounds. In addition, the unclassical hydrogen bonds of C-H…O and C-H…N are presented in the crystals except for the normal hydrogen bonds of N-H…O.

Efficient Synthesis,Crystal Structure and Antibacterial Activity of Two Novel Thieno[2,3-d]pyrimidin-4(3H)-one Derivatives

Two new thieno[2,3-d]pyrimidin-4（3H）-one derivatives,C24H22 Cl N3O2S（5a） and C25H25N3O2S（5b）,have been synthesized via a tandem aza-Wittig reaction.This tandem reaction has many attractive aspects such as easily accessible and versatile starting materials,mild conditions and high yields.Both compounds have been characterized by elemental analysis,HR-MS,IR,NMR spectra and X-ray single-crystal diffraction.Compound 5a crystallizes in monoclinic,space group P21/c with a = 9.986（3）,b = 14.263（4）,c = 15.530（5）A,β = 93.806（5）o,V = 2207.1（11） A^3,Mr = 451.96,Z = 4,Dc = 1.360 g/cm3,F（000） = 944,μ = 0.294 mm-1,Mo Kα radiation（λ = 0.71073 A）,the final R = 0.0444 and w R = 0.1219 for 3407 observed reflections with I 〉 2σ（I）.Compound 5bcrystallizes in triclinic,space group P1 with a = 8.974（4）,b = 10.766（5）,c = 12.260（6） A,β = 93.047（7）o,V = 1122.1（9） A^3,Mr = 431.54,Z = 2,Dc = 1.277 g/cm3,F（000） = 456,μ = 0.170 mm-1,Mo Kα radiation（λ = 0.71073 A）,the final R = 0.0378 and w R = 0.1072 for 3806 observed reflections with I 〉 2σ（I）.The preliminary antibacterial activities of 5a and 5b were investigated.Compound 5a showed 71.3% and 79.2% in vitro inhibition against Fusarium oxysporium and Rhizoctonia solani,respectively.Compound 5b showed 75.3% in vitro inhibition against Rhizoctonia solani.

Synthesis and Crystal Structure of a Novel Two-dimensional Layered Polymer [Zn(μ-O_2CCH=CHCO_2)(C_3H_4N_2)(H_2O)]_n

The title complex [Zn(-O2CCH=CHCO2)(C3H4N2)(H2O)]n was prepared by the reaction of zinc carbonate with maleic acid and imidazole in an aqueous-alcohol solution at 333 K, and its crystal structure has been solved by single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group Pc with a = 5.3858(7), b = 22.685(3), c = 7.6782(1) ? = 92.261(2)o, V = 937.4(2) 3, Z = 1, C14H16N4O10Zn2, Mr = 531.05, Dc = 1.882 g/cm3, = 2.623 mm1, F(000) = 532, the final R = 0.0372 and wR = 0.0930 for 1926 observed reflections with I>2s(I). The central zinc atom is five-coordinated in a distorted square pyramidal environment to three oxygen atoms of two different maleate ligands, a nitrogen atom of the imi- dazole ligand and an oxygen atom of water. In the complex two carboxylate groups of the maleate ligands have two coordination modes. One acts as a bidentate chelate ligand and the other a monoatomic monodentate ligand to bridge two zinc centers. As a result, 1-D infinite polymeric chains are formed, which are linked together by pairs of OH…O hydrogen bonds between the coordination water OH groups and carboxylate oxygen atoms to construct a 2-D layered polymer, and the layer structure is stabilized by p-p stacking of the imidozel ligands.

Synthesis and Crystal Structure of 2-Benzylamino-6-methyl-3-cyano-8- phenyl-5H-bispyrazolo[3,4-d,3',2'-b]pyrimidine

The title compound 2-benzylamino-6-methyl-3-cyano-8-phenyl-5H-bispyrazolo[3,4-d,3＇,2＇-b]pyrimidine crystallizes in orthorhombic, space group Pbca with a = 17.945（7）, b =10.862（4）, c = 19.481（7） A°, β = 90°, Z = 8, V = 1151.8（4） A°^3, Mr = 379.43, Dx = 1.327 g/cm^3,μ（MoKa） = 0.084 mm^-1, F（000） = 1584, the final R = 0.0513 and wR = 0.1128 for 2608 observed reflections （I 〉 2σ（I））. X-ray analysis reveals that the tricyclic portion of the molecule is effectively planar. In addition, there exist three intermolecular hydrogen bonds.

Synthesis,Crystal Structure and Anti-tumor Activity of 2-(2-Chloro-4-nitrophenyl)-4-(4-chlorophenyl)-3a,4-diethoxy-2,3,3a,4-tetrahydrochromeno[3,4-d][1,2,3]diazaphosphole

The title compound 2-（2-chloro-4-nitrophenyl）-4-（4-chlorophenyl）-3a,4- diethoxy- 2,3,3a, 4-tetrahydrochromeno[3,4-d][1,2,3]diazaphosphole 2 （C29H30Cl2N3O7P, Mr = 633.44） was synthesized and its structure was characterized by IR, MS, ^1H NMR, ^13C NMR, ^31p NMR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1^-, a = 9.1549（3）, b = 10.7168（4）, c = 17.6272（6）A, α = 102.9363（12）, β = 90.2713（9）, γ = 117.4265（10）°, V= 1484.41（9）A^3, Z= 2,μ（MoKa） = 0.323, F（000） = 658, Z= 2, De= 1.417 g/cm^3, the final R = 0.0687 and wR = 0.2066 for 4943 observed reflections （I 〉 2σ（I））. X-ray analysis reveals that the diazaphospholine ring is almost planar and the two ethoxy groups bonded on the 3a- and 4-positions are in trans configurations. Its antiproliferative activity was also tested in vitro against four human tumor cell lines.

Tunability of Photonic Band Gaps in One- and Two-dimensional Photonic Crystals Based on ZnS Particles Embedded in TiO2 Matrix

Using the Maxwell-GarneR theory, the evolution of the refractive index of titanium dioxide （TiO2） doped with zinc sulfide （ZnS） particles is presented. The presence of the nano-objects in the host matrix allows us to obtain a new composite material with tunable optical properties. We find that the filling factor of ZnS nanoparticles greatly alters photonic band gaps （PBGs）. We have calculated also the photonic band structure for electromagnetic waves propagating in a structure consisting of ZnS rods covered with the air shell layer in 2D hexagonal and square lattices by the finite difference time domain （FDTD） method. The rods are embedded in the TiO2 background medium with a high dielectric constant. Such photonic lattices present complete photonic band gaps （CPBGs）. Our results show that the existence of the air shell layer leads to larger complete photonic gaps. We believe that the present results are significant to increase the possibilities for experimentalists to realize a sizeable and larger CPBG.

A Zinc TTR Complex with a Novel 2-D Structure (TTR=3-Amino-1H-1,2,4-triazole)

The solvothermal reaction of 3-amino-1H-1,2,4-triazole （ttr） with Zn（ClO4）2·6H2O and NaCl in a 1：1：1 molar ratio gave a new complex [Zn（ttr）Cl]n with a 3-connected （4.82） 2-D structure. The layers stack in the -ABAB- way along the c axis with abundant hydrogen bonding interactions to form the crystal structure. The complex [Zn（ttr）Cl]n crystallizes in the orthorhombic space group Pbca with a = 9.369（1）, b = 10.049（1）, c = 11.905（1）A, V = 1120.9（3）A^3, Z = 8.00, C2N4H3ZnCl, Mr = 183.90, Dc = 2.180 g/cm^3,μ = 4.740 mm^-1, F（000） = 720, S = 1.059 and T = 293（2） K. The final R = 0.0662 and wR = 0.2457 for 956 observed reflections with Ⅰ〉 2σ（Ⅰ）, and R = 0.0689 and wR = 0.2504 for all data.

LiNbO_(3)棒辅助型As_(2)S_(3)光子晶体光纤中的超连续谱

为使中红外超连续谱谱宽连续可调,本文提出了一种以As_(2)S_(3)材料为基底材料,光轴方向与光纤的轴向一致的LiNbO_(3)晶体棒辅助型的光子晶体光纤。采用有限元法计算了外加轴向电场对光纤色散、有效模场面积以及非线性系数的影响,模拟了光脉冲在光纤中的传输演化,分析了外加轴向电场对超连续谱的谱宽和相干性的可调谐性。结果表明相同泵浦条件下光纤的占空比为0.6时超连续谱的谱宽与调谐范围均高于其他结构。当光纤中注入脉冲的峰值功率为5 kW,脉冲宽度100 fs,中心波长3.5μm的泵浦脉冲后,电场强度为40×10^(8) V/m时光纤可产生超连续谱谱宽达到2.2420μm,比未加电场时增大176.30 nm。外加电场会使超连续谱在长波段提高超连续谱的相干性,相干因子趋近于1。可以获得谱宽连续可调的中红外超连续光源,并在传感检测与生物医学等领域有潜在的应用。

反蛋白石型黑TiO_(2)光子晶体的制备与光催化性能

采用硬模板法制备了反蛋白石型TiO_(2)光子晶体,对其氢化处理后得到黑TiO_(2)光子晶体(H-IOTiO_(2))。通过X射线衍射、扫描电子显微镜、X射线光电子能谱分析等手段,确定了H-IOTiO_(2)表面存在大量Ti^(3+)和O空位缺陷,导致吸收光谱的红移。催化剂的光催化活性采用有机染料的光催化降解来评价。发现染料罗丹明B(RhB)的降解符合拟一级动力学,H-IOTiO_(2)表现出最强的光催化活性(速率常数0.033min^(-1)),分别是是未热处理催化剂TiO_(2)(速率常数0.014min^(-1))和空气热处理催化剂(速率常数0.028min^(-1))活性的2.4和1.2倍。自由基淬灭实验证实:H-IOTiO_(2)在光照下能够产生更多的活性氧化基团,特别是·O_(2)^(-)和·OH自由基;证实了H-IOTiO_(2)表面缺陷的存在可以显著加速表面氧还原过程,最终体现为样品光催化活性的显著提升。

SiO_(2)光子晶体的制备及其在增强上转换发光的应用

用改进的St?ber法制备了均一分散的SiO_(2)微球。探讨了不同温度环境和正硅酸乙酯(TEOS)的用量对生成微球粒径大小的影响。用扫描电子显微镜、分光光度计、X射线衍射仪紫外-近红外吸收发射光谱仪等仪器对粉末和薄膜的形貌与光学性能进行表征。结果表明:随着温度的增加,微球的粒径不断减小。TEOS试剂的用量增加,生成微球的粒径也随之增加。讨论了不同温度的自组装环境对光子晶体自组装的影响。结果表明,当自组装温度为55℃时制备的二氧化硅光子晶体薄膜质量最高。用980 nm激发光对旋涂在玻璃基板和光子晶体上的上转换薄膜进行发光测试,红光发光增强1.72倍,绿光发光增强1.93倍。这是由于带隙位于激发光波段的光子晶体表面具有高光子态密度,能够增强发光粒子周围电磁场强度,提高了电子跃迁的几率,从而增强了荧光强度。

MoO_(2)薄膜涂覆的超高灵敏度光子晶体光纤传感器

Au、Ag等贵金属在光子晶体光纤中表现出了优良的性能,但高昂的成本限制了其进一步发展,因此迫切需要开发具有低成本和高电荷载流子密度的新型表面等离子体激元材料。提出了一种廉价的基于MoO_(2)纳米薄膜涂覆的超高灵敏度D型光子晶体光纤传感器,该传感器实现了分析物折射率从1.38~1.43范围的传感检测,并且通过调整光纤结构参数得到了最优结构,实现了x偏振方向高达24000 nm/RIU的超高平均灵敏度,表明MoO_(2)作为等离子传感材料在光纤传感领域有极大的应用潜力。