1,3-Thiazole as Suitable Antenna Ligand for Lanthanide Photoluminescence in [LnCl3(thz)4]·0.5thz, Ln = Sm, Eu, Gd, Tb, Dy

The series of luminescent monomeric lanthanide thiazole complexes [LnCl3(thz)4]⋅0.5thz (Ln = Sm, Eu, Gd, Tb, Dy; thz=1,3-thiazole) has been synthesised and characterised by powder and singlecrystal X-ray diffraction, IR and photoluminescence spectroscopy, DTA/TG as well as elemental analysis. The colourless compounds exhibit photoluminescence in the visible region with varying quantum efficiencies up to QY = 48% for [TbCl3(thz)4]⋅0.5thz. Both, the lanthanide ions as well as the thiazole ligand contribute to the luminescence. Excitation can be achieved via intra-4 f transitions and by exciting the ligand, emission is observed mainly from the lanthanide ions again by 4 f transitions. Thiazole can transfer energy to the lanthanide ions, which further feeds the lanthanide emission by an efficient antenna effect even at room temperature. The lanthanide ions show pentagonalbipyramidal coordination by three chloride anions and four N atoms of 1,3-thiazole, which leads to a strong 5D0 →7F4 transition for europium. Significant differences arise as compared to thiophene complexes because no sulphur atom is involved in the metal coordination, as the thiazole ligand is solely coordinated via its nitrogen function.

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Effect of trytophan as dopant on potassium acid phthalate single crystals

10.31221/osf.io/cn28k ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Single Crystals ◽

Room Temperature ◽

Visible Region ◽

X Ray Diffraction ◽

X Ray ◽

Slow Evaporation Technique ◽

Absorption Studies ◽

Evaporation Technique ◽

Potassium Acid Phthalate ◽

Acid Phthalate

Optically transparent single crystals of potassium acid phthalate (KAP, 0.5 g) 0.05 g and 0.1 g (1 and 2 mol %) trytophan were grown in aqueous solution by slow evaporation technique at room temperature. Single crystal X- ray diffraction analysis confirmed the changes in the lattice parameters of the doped crystals. The presence of functional groups in the crystal lattice has been determined qualitatively by FTIR analysis. Optical absorption studies revealed that the doped crystals possess very low absorption in the entire visible region. The dielectric constant has been studied as a function of frequency for the doped crystals. The thermal stability was evaluated by TG-DSC analysis.

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Growth and Magneto-Optical Properties of CaTbAlO4 Crystal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.1722 ◽

2011 ◽

Vol 306-307 ◽

pp. 1722-1727 ◽

Cited By ~ 2

Author(s):

Man Mei ◽

Li Li Cao ◽

Yan He ◽

Ru Ru Zhang ◽

Fei Yun Guo ◽

...

Keyword(s):

Optical Properties ◽

Single Crystal ◽

Room Temperature ◽

Near Infrared ◽

Visible Region ◽

Czochralski Method ◽

Optical Devices ◽

X Ray Diffraction ◽

X Ray ◽

Infrared Spectral

The calcium terbium aluminate (CaTbAlO4) single crystal was grown by Czochralski method successfully for the first time.The structure of the crystal was determined by X-ray diffraction analysis.The transmission spectrum of the crystal was measured at room temperature at the wavelength of 400-1500nm.The specific Faraday rotation of the single crystal was surveyed at room temperature at the wavelength 532nm, 633nm, and 1064nm respectively.The Verdet constants of the CaTbAlO4 crystal are calculated and the results show that the Verdet constants of CaTbAlO4 are around 110% higher than that of TGG in the visible and near-infrared spectral region.Therefore,crystal CaTbAlO4 can be promising material for the fabrication of magneto-optical devices in the visible region.

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A three-dimensional cyanide-bridged heterometallic coordination polymer: poly[[diacetonitrilediaqua[μ2-3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine-κ4N1,N6:N3,N4]tetra-μ-cyanido-tetracyanidodimanganese(II)molybdate(IV)] dihydrate]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614020117 ◽

2014 ◽

Vol 70 (11) ◽

pp. 1029-1032 ◽

Cited By ~ 2

Author(s):

Xiao-Juan Xu

Keyword(s):

Magnetic Properties ◽

Ir Spectroscopy ◽

Coordination Polymer ◽

Elemental Analysis ◽

Room Temperature ◽

Three Dimensional ◽

Antiferromagnetic Coupling ◽

X Ray Diffraction ◽

X Ray ◽

Magnetic Investigation

A metal coordination polymer, {[Mn2Mo(CN)8(C12H8N6)(CH3CN)2(H2O)2]·2H2O}n, has been synthesized by the reaction of Mn(ClO4)2·6H2O with 3,6-bis(pyridin-2-yl)-1,2,4,5-tetrazine (bptz) and (Bu3N)3[Mo(CN)8] at room temperature. The polymer was characterized by IR spectroscopy, elemental analysis and X-ray diffraction, and the magnetic properties were also investigated. The X-ray diffraction analysis reveals that the compound is a new three-dimensional coordination polymer with a PtS-type network. Magnetic investigation shows antiferromagnetic coupling between adjacent Mn2+cations.

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EFFECT OF SURFACE MODIFICATION ON STRUCTURAL, OPTICAL AND AMMONIA SENSING PROPERTIES OF INDIUM OXIDE FILMS

Surface Review and Letters ◽

10.1142/s0218625x11014710 ◽

2011 ◽

Vol 18 (05) ◽

pp. 197-202

Author(s):

AMANDEEP KAUR BAL ◽

R. K. BEDI

Keyword(s):

Indium Oxide ◽

Room Temperature ◽

Visible Region ◽

X Ray Diffraction ◽

X Ray ◽

Ammonia Sensing ◽

Small Grains ◽

Prominent Peak ◽

Scanning Electron ◽

Effect Of Surface

Indium oxide (In2O3) films have been prepared by thermal oxidation of pre-deposited indium films onto glass substrate kept at room temperature (35°C). These films were dipped into an aqueous solution (0.1 M) of lithium chloride (LiCl) and aluminum chloride (AlCl3) followed by being fired at 500°C. Based on X-ray diffraction results, it has been observed that pure and Li modified In2O3 films are polycrystalline in nature while Al modified In2O3 film has a prominent peak corresponding to 222 plane of In2O3 . Field emission scanning electron microscopy of pure film shows smaller grains which get transformed to bigger ones for Li modified In2O3 film. In case of Al modified In2O3 film agglomerated small grains are observed. This film also reveals the response of 60% for 100 ppm of ammonia vapors at room temperature. The transparency increased from 23–36% to 53–67% in visible region with Li modification of pure In2O3 film.

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Spontaneous ferromagnetism at room temperature in oxygen-rich dicalcium cuprate Ca2CuO3+δ

Journal of Materials Research ◽

10.1557/jmr.1996.0227 ◽

1996 ◽

Vol 11 (7) ◽

pp. 1804-1809 ◽

Cited By ~ 1

Author(s):

Mahjoub A. Abdelgadir ◽

Richard S. Burrows ◽

Darl H. McDaniel

Keyword(s):

Saturation Magnetization ◽

Elemental Analysis ◽

Applied Field ◽

Room Temperature ◽

Magnetic Impurity ◽

Oxygen Depletion ◽

Excess Oxygen ◽

X Ray Diffraction ◽

X Ray ◽

Square Planar

Stoichiometric Ca2CuO3, having square-planar Cu-chains [C. L. Teske and H. Müller-Buschbaum, Z. Anorg. Allg. Chem. 379, 234 (1970); M. Hjorth and J. Hyldtoft, Acta Chem. Scand. 44, 516 (1990)], is expectedly antiferromagnetic due to 1D intrachain superexchange [K. Okuda, S. Noguchi, K. Konishi, H. Deguchi, and K. Takeda, J. Magn. Magn. Mater. 104–107, 817 (1992)]. Nonetheless, we report remarkable spontaneous ferromagnetism at 293 K after sintering, prominently in oxygen. This apparently introduced excess oxygen at vacant quasioctahedral sites, promoting spin-flip and ferromagnetic interchain coupling. Thermogravimetry (TGA) revealed excess oxygen, ≈0.17 O/Cu. X-ray diffraction (XRD) yielded a comparatively smaller unit cell. Ferromagnetism disappeared by oxygen depletion, mimicking reported nonmagnetism of Ca2CuO3−δ [Okuda et al. (1992)]. Elemental analysis showed insignificant magnetic impurity traces. Tc ranged between 680 K and 723 K, depending on freshness and purity. Saturation magnetization varied with processing, optimally 0.30 A · m2/kg at 1.0 T applied field. Coercivity and remanence varied with purity.

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Synthesis, Structure and Photoluminescence of a Potential Luminescent Material of Mn(II) Coordination Polymer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.528.206 ◽

2012 ◽

Vol 528 ◽

pp. 206-209 ◽

Cited By ~ 1

Author(s):

Xiu Ling Zhang ◽

Kai Cheng ◽

Yu Lan Song

Keyword(s):

Hydrogen Bonding ◽

Solid State ◽

Coordination Polymer ◽

Single Crystal ◽

Elemental Analysis ◽

Room Temperature ◽

Luminescent Material ◽

X Ray Diffraction ◽

X Ray ◽

1D Chain

A new coordination polymer [Mn3(IP)(4,4'-obb)3]n (1) (4,4'-obb = 4,4'-Oxybisbenzoic acid, IP = 1H-imidazo[4,5-f][1,10]-phenanthroline) was synthesized and characterized by IR, elemental analysis and X-ray diffraction. Single-crystal X-ray analyses revealed that the compound demonstrates 1D structure in which the Mn2+ centers are connected via 4,4'-obb anions into 1D chain, the chains are further connected via hydrogen - bonding and π ••• π interactions. In addition, the photoluminescence for compound 1 is also investigated in the solid state at room temperature.

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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Electron Microscope study of commensurate-incommensurate phase transition in BaZnGeO4

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173996 ◽

1990 ◽

Vol 48 (4) ◽

pp. 172-173

Author(s):

Naoki Yamamoto ◽

Makoto Kikuchi ◽

Tooru Atake ◽

Akihiro Hamano ◽

Yasutoshi Saito

Keyword(s):

Phase Transition ◽

Electron Microscope Study ◽

Room Temperature ◽

Hexagonal Lattice ◽

Ferroelectric Materials ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Periodic Arrays ◽

Modulation Wave Vector

BaZnGeO4 undergoes many phase transitions from I to V phase. The highest temperature phase I has a BaAl2O4 type structure with a hexagonal lattice. Recent X-ray diffraction study showed that the incommensurate (IC) lattice modulation appears along the c axis in the III and IV phases with a period of about 4c, and a commensurate (C) phase with a modulated period of 4c exists between the III and IV phases in the narrow temperature region (—58°C to —47°C on cooling), called the III' phase. The modulations in the IC phases are considered displacive type, but the detailed structures have not been studied. It is also not clear whether the modulation changes into periodic arrays of discommensurations (DC’s) near the III-III' and IV-V phase transition temperature as found in the ferroelectric materials such as Rb2ZnCl4.At room temperature (III phase) satellite reflections were seen around the fundamental reflections in a diffraction pattern (Fig.1) and they aligned along a certain direction deviated from the c* direction, which indicates that the modulation wave vector q tilts from the c* axis. The tilt angle is about 2 degree at room temperature and depends on temperature.

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Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

10.26434/chemrxiv.7092263.v1 ◽

2018 ◽

Author(s):

Katherine Marczenko ◽

James Goettel ◽

Gary Schrobilgen

Keyword(s):

Room Temperature ◽

Triphenylphosphine Oxide ◽

Donor Ligands ◽

Mechanical Shock ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination ◽

Xenon Trioxide ◽

Distorted Octahedra ◽

Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO3 was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, the solid [(C6H5)3PO]2XeO3, [(CH3)2SO]3(XeO3)2, and (C5H5NO)3(XeO3)2 adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are air-stable whereas [(CH3)2SO]3(XeO3)2 slowly decomposes over several days and [(CH3)2CO]3XeO3 undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C6H5)3PO]2XeO3 is a distorted square pyramid which provides the first example of a five-coordinate XeO3 adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO3. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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Structural and Enhanced Optical Properties of Stabilized γ‒Bi2O3 Nanoparticles: Effect of Oxygen Ion Vacancies

Nanomaterials ◽

10.3390/nano10061023 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1023 ◽

Cited By ~ 2

Author(s):

Ashish Chhaganlal Gandhi ◽

Chia-Liang Cheng ◽

Sheng Yun Wu

Keyword(s):

Room Temperature ◽

Excess Oxygen ◽

Ambient Atmosphere ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Band Emission ◽

Oxygen Ion ◽

Integrated Intensity ◽

Effect Of Oxygen

We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.

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