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Spectroscopic Properties (spectroscopic + property)
Selected AbstractsStructures, Redox and Spectroscopic Properties of PdII and PtII Complexes Containing an Azo FunctionalityEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 17 2009Sayak Roy No abstract is available for this article. [source] Phase Relations Between ,-Tricalcium Phosphate and Hydroxyapatite with Manganese(II): Structural and Spectroscopic PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2006Isaac Mayer Abstract The preparation of Mn-containing ,-tricalcium phosphate (,-TCP) samples was achieved in two ways: a) transformation of precipitated Mn-containing calcium hydroxyapatite (HA) to ,-TCP by heating at 1100 °C, and b) preparation by solid-state reaction of a mixture of CaCO3, (NH4)2HPO4, and Mn(NO3)2 at 1100 °C. Powder X-ray diffraction (XRD) analyses of the samples, obtained by both methods, show well-defined patterns with structural data of the rhombohedral R3c, ,-TCP phase. The calculated lattice constants are smaller than those known for ,-Ca3(PO4)2 because of substitution of Ca2+ by Mn2+. EPR spectroscopy indeed reveals that manganese is divalent in the samples. Apparently, the Ca(5) site in the ,-TCP structure is occupied by Mn2+. The distribution of Mn2+ between the ,-TCP and the HA phase in the case of preparation (b) was studied by EPR spectroscopy, and a pronounced preference for the former lattice was found. Micron- and submicron-sized crystals with visible faces were observed by TEM in the case of ,-TCP prepared by solid-state reaction, and large micron-sized, droplike-shaped crystals, sensitive to beam radiation, were found in the case of samples prepared by heating HA at elevated temperatures. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis, Structure and Spectroscopic Properties of Novel9,10-Bis{[6-(diphenylphosphanyl)-2-pyridylmethyl]propylaminomethyl}anthracene-Bridged Group 11 Metal (M = CuI and AgI) Dinuclear ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2005Hu Xu Abstract Dinuclear complexes [M2(,-BPNNAn)]X2 (M = CuI, X = ClO4,1, X = BF4,2; M = AgI, X = BF4,3, X = ClO4,4) have been prepared by treating 9,10-bis{[6-(diphenylphosphanyl)-2-pyridylmethyl]propylaminomethyl}anthracene (BPNNAn) with M(CH3CN)4X in CH2Cl2. The structures of complexes 1, 2 and 3 have been determined by single-crystal X-ray diffraction studies. In the complexes, BPNNAn acts as a chelating ligand and two metal ions riding on two bridgehead carbon atoms in the anthracene group leads to the deformation of the anthracenyl ring. The Cu,Arene charge transfer interaction is observed from the nonfluorescent emission of Cu complex 1, while the Ag complex 3 exhibits dual emission at high concentrations in a CH2Cl2 solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Spectroscopic Properties and Local Structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) GlassesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2003Woon Jin Chung Spectroscopic properties and local structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) glasses were investigated using fluorescence measurements and several spectroscopic methods. Fluorescence from Eu3+:5D0,7F2 was observed only from glasses with CsBr/Ga ratios greater than unity and disappeared at temperatures above 140 K. Phonon sideband (PSB) spectra revealed that Eu3+ ions are located next to halogen ions, which form part of well-structured complexes such as EuCl3, tetrahedral [GaS3/2Cl],, subunits and/or Ga2Cl6. These new bonds showed reduced coupling strength compared with Eu3+,S bonds in Ge,Ga,S glass. Fluorescence line narrowing experiments showed little site-to-site variation of Eu3+ ions. [source] Spectroscopic Properties and Thermal Stability of Er3+ -Doped Germanotellurite Glasses for Broadband Fiber AmplifiersJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2001Xian Feng The thermal stability and spectroscopic properties of Er2O3 -doped TeO2,GeO2,ZnO,Na2O,Y2O3 glasses for 1.5 ,m fiber amplifiers were investigated. The thermal stability of the 75TeO2·20ZnO· 5Na2O glass was improved by introducing GeO2 and Y2O3. The radiative transition and the nonradiative transition have a dominant influence on the 4I13/2 level lifetime of Er3+ in high- and low-GeO2 regions, respectively. Adding Y2O3 increases the 4I13/2 level lifetime of Er3+ significantly. The Judd,Ofelt (J-O) parameter ,6 shows a strong correlation with the 1.5 ,m emission bandwidth; and the larger the ,6, the wider the bandwidth. [source] Spectroscopic Properties of Quercetin Derivatives, Quercetin-3- O -rhamnoside and Quercetin-3- O -rutinoside, in Hydro-organic Mixed SolventsPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2009Hai-Bo Liu The characteristic fluorescence properties of quercetin-3- O -rhamnoside (QCRM) and quercetin-3- O -rutinoside (QCRT) were studied in CH3OH,H2O and CH3CN,H2O mixed solvents. Although QCRM and QCRT are known as nonfluorescent molecules, significant fluorescence emissions were discovered at 360 nm in CH3OH and CH3CN when they were promoted to the second excited state. The emission band is broad and structureless and the intensity decreases quickly as the H2O composition in the solvent increases. When the amount of H2O exceeds 60% in both mixed solvents, this emission disappears due to the formation of the distorted excited state. This state will be formed due to the strong intermolecular hydrogen bonding between the polar groups of solute and H2O. As the composition of CH3OH or CH3CN in solvent becomes large, the number of molecules having several intramolecular hydrogen bonding increases. Some of these molecules will be changed to a fluorescent species during the decay process, after excitation. The theoretical calculation further supports these results. The change of the lifetimes, quantum yields, and radiative and nonradiative rate constants of molecules was also examined as a function of solvatochromic parameters for CH3OH,H2O and CH3CN,H2O. [source] Spectroscopic Properties of Various Quinolone Antibiotics in Aqueous,organic Solvent Mixtures¶PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2004Hyoung-Ryun Park The spectroscopic properties of enoxacin (ENO), oxolinic acid (OXO) and nalidixic acid (NAL) were studied in various H2O-CH3OH and H2O-CH3CN mixed solvents because these solvents were thought to behave as a biological mimetic system. ENO has piperazinyl group, but OXO and NAL do not have this substituent. The fluorescence emission spectra of ENO were very sensitive to the composition of the solvents. In the Lippert-Mataga analysis of the steady-state fluorescence data, clear reverse solvatochromism was exhibited for ENO in both mixed solvents. This observation can be explained using the excited state twisted intramolecular charge transfer (TICT) from the nitrogen of the piperazinyl group to the keto oxygen. Theoretical calculations further support this observation. The nonradiative and radiative rate constants of these molecules were analyzed as a function of dipolarity,polarizability (,*) and hydrogen bond donor acidity (,) of the mixed solvents. These results for ENO were consistent with the suggested mechanism of the TICT very well. The influence of bulk dielectric effect was more significant relative to the specific hydrogen bonding interactions. The emission spectra of OXO and NAL do not exhibit any characteristic responses to the properties of the solvent. [source] ChemInform Abstract: Synthesis, Structure, and Spectroscopic Properties of the New Lanthanum(III) Fluoride Oxomolybdate(VI) La3FMo4O16.CHEMINFORM, Issue 25 2010Ingo Hartenbach Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Ab initio Prediction of the Structure and Vibration,Rotation Spectroscopic Properties of Li2OH and Li2OH+.CHEMINFORM, Issue 24 2008Artur Gertych Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis and VUV,UV Spectroscopic Properties of Rare Earth Borosilicate Oxyapatite: RE5Si2BO13: Ln3+ (RE: La, Gd, Y; Ln: Eu, Tb).CHEMINFORM, Issue 2 2008Jun-Lin Yuan Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Syntheses, Structures, and Spectroscopic Properties of Push-Pull Heteroquinoid Compounds.CHEMINFORM, Issue 30 2007Shinobu Inoue Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Electronic States and Spectroscopic Properties of SiTe and SiTe+CHEMINFORM, Issue 5 2007Surya Chattopadhyaya Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Structural and Spectroscopic Properties of Pure and Doped Ba6Ti2Nb8O30 Tungsten Bronze.CHEMINFORM, Issue 49 2006V. Massarotti Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] The New Silver Thiostannate (1,4-dabH2)Ag2SnS4: Solvothermal Synthesis, Crystal Structure and Spectroscopic Properties.CHEMINFORM, Issue 46 2006Nicole Pienack Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis and Spectroscopic Properties of a Covalently Linked Porphyrin,Fullerene C60 Dyad.CHEMINFORM, Issue 41 2006M. Elisa Milanesio Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Crystal Chemistry and Spectroscopic Properties of ScAuSn, YAuSn, and LuAuSn.CHEMINFORM, Issue 28 2006C. Peter Sebastian Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis, Crystal Structure Determination from X-Ray Powder Diffractometry and Vibrational Spectroscopic Properties of Mg[N(CN)2]2×4H2O.CHEMINFORM, Issue 36 2005Elisabeth Irran Abstract For Abstract see ChemInform Abstract in Full Text. [source] Spectroscopic Properties of Er3+ in LiErP4O12 and LiErYP4O12 Single CrystalsCHEMINFORM, Issue 30 2005Bogdan M. Angelov Abstract For Abstract see ChemInform Abstract in Full Text. [source] Magnetic and Spectroscopic Properties of NdTSn (T: Ag, Au) Compounds.CHEMINFORM, Issue 12 2005K. Latka Abstract For Abstract see ChemInform Abstract in Full Text. [source] Electronic Structures and Spectroscopic Properties of 6,-Electron Ring Molecules and Ions E2N2 and E2+4 (E: S, Se, Te)CHEMINFORM, Issue 36 2004Heikki M. Tuononen Abstract For Abstract see ChemInform Abstract in Full Text. [source] Global Minimum-Energy Structure and Spectroscopic Properties of I2.,,n,H2O Clusters: A Monte Carlo Simulated Annealing StudyCHEMPHYSCHEM, Issue 1 2010Arup Kumar Pathak Abstract The vibrational (IR and Raman) and photoelectron spectral properties of hydrated iodine-dimer radical-anion clusters, I2.,,n,H2O (n=1,10), are presented. Several initial guess structures are considered for each size of cluster to locate the global minimum-energy structure by applying a Monte Carlo simulated annealing procedure including spin,orbit interaction. In the Raman spectrum, hydration reduces the intensity of the II stretching band but enhances the intensity of the OH stretching band of water. Raman spectra of more highly hydrated clusters appear to be simpler than the corresponding IR spectra. Vibrational bands due to simultaneous stretching vibrations of OH bonds in a cyclic water network are observed for I2.,,n,H2O clusters with n,3. The vertical detachment energy (VDE) profile shows stepwise saturation that indicates closing of the geometrical shell in the hydrated clusters on addition of every four water molecules. The calculated VDE of finite-size small hydrated clusters is extrapolated to evaluate the bulk VDE value of I2., in aqueous solution as 7.6 eV at the CCSD(T) level of theory. Structure and spectroscopic properties of these hydrated clusters are compared with those of hydrated clusters of Cl2., and Br2.,. [source] Spectroscopic Properties in the Liquid Phase: Combining High-Level Ab Initio Calculations and Classical Molecular DynamicsCHEMPHYSCHEM, Issue 1 2006Michele Pavone Dr. Abstract We present an integrated computational tool, rooted in density functional theory, the polarizable continuum model, and classical molecular dynamics employing spherical boundary conditions, to study the spectroscopic observables of molecules in solution. As a test case, a modified OPLS-AA force field has been developed and used to compute the UV and NMR spectra of acetone in aqueous solution. The results show that provided the classical force fields are carefully reparameterized and validated, the proposed approach is robust and effective, and can also be used by nonspecialists to provide a general and powerful complement to experimental techniques. [source] Size-Dependent Spectroscopic Properties and Thermochromic Behavior in Poly(substituted thiophene) NanoparticlesCHEMPHYSCHEM, Issue 10 2004Naonori Kurokawa Dr. Nanoparticles are attractive nanomaterials, since they exhibit unique physical and chemical properties. We have found that poly(substituted thiophene) nanoparticles, ranging in size from several tens to hundreds of nanometers, exhibit size-dependent characteristic spectroscopic properties and thermochromic behavior, which can be explained by distorted polymer conformations in the surface layer (see graphic). [source] Spectroscopic properties of La3Ga5SiO14:Er3+ (1%) crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 11 2006Zeng M. Wang Abstract Single crystals of Erbium (Er) doped La3Ga5SiO14 (LGS) have been grown along c-axis by using the Czochralski method. The absorption and fluorescence spectra of LGS: Er3+ single crystals have been measured and analyzed according to the Judd-Ofelt theory. When applied, the following spectral parameters have been obtained: intensity parameters ,t, ,2= 2.741674×10 -20cm2, ,4= 0.66934×10 -20 cm2 and ,6= 0.592591×10 -20 cm2, radiative transition probabilities AJ,J", PJ,J". The radiative lifetime of levels 4I13/2, 4H9/2, 4S3/2 are 11.333ms, 0.447ms and 0.704ms, respectively. The fluorescence branching ratios and the integrated emission cross sections are also calculated. The results suggest that LGS: Er crystals have potential applications as a laser material. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] 1,6- and 1,7-naphthyridines.JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2005A series of 8-hydroxy-1,6-naphthyridin-5(6H)-one-7-carboxamides 1 and the isomeric 5-hydroxy-1,7-naphthyridin-8(7H)-one-6-carboxamides 2 were synthesized. N -Lactam unsubstituted compounds 1a-c and 2a,b were obtained by alkoxide-induced rearrangement of the corresponding quinolinimidoacetamides 3. Compounds 1e,f and 2e,f were synthesized by heterocyclization of the corresponding quinolinamic esters 6 and 7. Spectroscopic properties (uv, ir, 1H and 13C nmr and ms) were analyzed and the proposed structures confirmed. [source] Electronic Structure and Bonding of All Crystalline Phases in the Silica,Yttria,Silicon Nitride Phase Equilibrium DiagramJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2004Wai-Yim Ching This paper reviews the structures and properties of 10 binary, ternary, and quaternary crystals within the equilibrium phase diagram of the SiO2,Y2O3,Si3N4 system. They are binary compounds SiO2, Y2O3, Si3N4; ternary compounds Si2N2O, Y2Si2O7, and YSi2O5; and quaternary crystals Y2Si3N4O3 (M-melilite), Y4Si2O7N2, (N-YAM), YSiO2N (wallastonite), and Y10(SiO4)6N2 (N-apatite, N-APT). Although the binary compounds are well-known and extensively studied, the ternary and the quaternary crystals are not. Most of the ternary and the quaternary crystals simply have been referenced as secondary phases in the processing of nitrogen ceramics. Their crystal structures are complex and not precisely determined. In the quaternary crystals, there exists O/N disorder in that the exact atomic positions of the anions cannot be uniquely determined. It is envisioned that a variety of cation,anion bonding configurations exist in these complex crystals. The electronic structure and bonding in these crystals are, therefore, of great interest and are indispensable for a fundamental understanding of structural ceramics. We have used ab initio methods to study the structure and bonding properties of these 10 crystals. For crystals with unknown or incomplete structural information, we use an accurate total energy relaxation scheme to obtain the most likely atomic positions. Based on the theoretically modeled structures, the electronic structure and bonding in these crystals are investigated and related to various local cation,anion bonding configurations. These results are presented in the form of atom-resolved partial density of states, Mulliken effective charges, and bond order values. It is shown that Y,O and Y,N bonding are not negligible and should be a part of the discussion of the overall bonding schemes in these crystals. Spectroscopic properties in the form of complex, frequency-dependent dielectric functions, X-ray absorption near-edge structure (XANES), and the electron energy-loss near-edge structure (ELNES) spectra in these crystals also are calculated and compared. These results are discussed in the context of specific bonding configurations between cations (silicon and yttrium) and anions (oxygen and nitrogen) and their implications on intergranular thin films in polycrystalline Si3N4 containing rare-earth elements. [source] Spectroscopic Properties and Local Structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) GlassesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2003Woon Jin Chung Spectroscopic properties and local structure of Eu3+ in Ge,Ga,S,CsBr (or CsCl) glasses were investigated using fluorescence measurements and several spectroscopic methods. Fluorescence from Eu3+:5D0,7F2 was observed only from glasses with CsBr/Ga ratios greater than unity and disappeared at temperatures above 140 K. Phonon sideband (PSB) spectra revealed that Eu3+ ions are located next to halogen ions, which form part of well-structured complexes such as EuCl3, tetrahedral [GaS3/2Cl],, subunits and/or Ga2Cl6. These new bonds showed reduced coupling strength compared with Eu3+,S bonds in Ge,Ga,S glass. Fluorescence line narrowing experiments showed little site-to-site variation of Eu3+ ions. [source] Tellurite glass lasers operating close to 2, mLASER PHYSICS LETTERS, Issue 3 2010B. Richards Abstract Recent work in the area of Tm3+ and Ho3+ -doped tellurite fibre and bulk glass lasers operating close to 2 , m is reviewed. Spectroscopic properties of these doped glasses are discussed as well as the relevant pump schemes and energy transfer processes involved. Results of continuous wave (CW) and Q-switched Tm3+ and Ho3+ -doped tellurite fibre lasers are then presented and discussed. Finally, the results of tellurite bulk glass laser experiments conducted to date are reported. (© 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Spectroscopic properties of Yb3+ -doped Ca4Gd0.5Y0.5O(BO3)3 single crystalsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 6 2010Yan Zhang Abstract Yb3+ -doped Ca4Gd0.5Y0.5O(BO3)3 single crystals with good optical quality have been grown by the Czochralski method. The grown crystal was characterized using X-ray powder diffraction. The polarized absorption and emission spectra and fluorescence lifetime of anisotropic monoclinic crystal Yb3+: Ca4Gd0.5Y0.5O(BO3)3 (Yb: GdYCOB) have been measured. Based on the absorption and emission spectra, the Stark energy-level distribution was located. The spectrum and laser parameters of Yb3+: Ca4Gd0.5Y0.5O(BO3)3 (Yb: GdYCOB) crystal have been calculated. [source] Site-Selective Ser-Hydrolase Labelling with a Luminescent Organometallic NCN,Platinum ComplexEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2010Birgit Wieczorek Abstract The synthesis, spectroscopic properties and protein-binding studies of a novel luminescent organometallic NCN,platinum complex are described. The luminescent organometallic complex was linked to a serine hydrolase reactive phosphonate group by means of click chemistry, and was exploited in serine hydrolase specific-binding studies using gel electrophoresis. The NCN,platinum protein label was found to be a robust dye with absorbance and emission maxima between 374,380 and 482,493 nm, respectively, and quantum yields between 0.04 and 0.15. [source] | |||||||||||||||||||||||||||||||||||||