- SPECTROSCOPIC PROPERTIES OF THE Eu3+ ION IN THE 3Eu(NCS)6 CRYSTAL
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The IR Raman and fluorescence spectra of Eu3+ in the 3Eu(NCS)6 crystal are reported.The results indicate that only one point symmetry of Eu3+ ion is present in the crystal.The presence of the 5D0 -> 7F0 transition in the fluorescence spectrum and the lack of strong vibronic lines indicates that the local symmetry of Eu3+ ion is lowered from Oh.The temperature dependence of fluorescence lifetimes of %&D0 level has been measured.The mechanism of fluorescence quenching is briefly discussed.
- Strek, W.,Mugenski, E.,Cywinski, R.,Hanuza, J.,Jezowska-Trzebiatowska, B.,Maghrawy, H.
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- A Comperative Multinuclear 1H, 13C, and 15N Magnetic Resonance Study of Organic Thiocyanates and Isothiocyanytes
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1H, 13C, and 15N n,m,r, spectra of thiocyanato (RSCN) and isothiocyanato (RNCS) compounds, especially for the vinylic series R1C(SCN)=CHR2 and R1C(NCS)=CHR2, are reported. 15N Chemical shifts of thiocyanates (? ca. -100 p.p.m.) and of isothiocyanates (? ca. -275 p.p.m.) are very different, the value for the thiocyanate ion (SCN)- being intermediate (? -165 p.p.m.).Comparison of the spectra of vinyl thiocyanates with those of the corresponding saturated compounds suggests that the SCN group exerts both attractive ? and ? effects on the C=C bond mainly through the intervention of the d orbitals of the S atoms.The NCS group appears to be slightly electron donating towards the double bond.Solvent effects on the 15N chemical shift of BunSCN and BunNCS are discussed in terms of Taft's linear solvation energy relationships.
- Giffard, Michel,Cousseau, Jack,Martin, Gerard Jean
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- Ion exchange synthesis and thermal characteristics of some [N +4444] based ionic liquids
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Eight salts, derived from tetrabutylammonium cation [N+ 4444] and inorganic anions like BF4-, NO 3-, NO2-, SCN-, BrO 3-, IO3-, PF6- and HCO3- were synthesized using the ion exchange method. These ionic liquids (ILs) were characterized using thermogravimetry, differential scanning calorimetry and infrared spectroscopy. Thermophysical properties such as density, volume expansion, heat of fusion, heat of solid-solid transitions, specific heat capacity and thermal energy storage capacity were determined. The total of heat of solid-solid transitions observed below the melting points exceeded the heat of fusion in some cases. The thermal conductivity of the samples was determined both in solid and liquid phases. High values of thermal energy storage capacity and handsome liquid phase thermal conductivities made many of the ionic liquids under investigation were recommended as Thermal Energy Storage Devices (TESDs) as well as heat transfer fluids.
- Bhatt, Vasishta D.,Gohil, Kuldip
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- PYRIDINE DERIVATIVE AND ITS COMPLEX
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A pyridine derivative exhibiting a photoelectric conversion is represented by formula (I) wherein each of R1, R2, R3, R4 is independently —OR′, —COOR′, —CONR′, —CHO, —CH2OR′, —CN, an alkyl group whose carbon number ranges from 1 to 20 inclusive, or —COONR′4, wherein R′ is a hydrogen, or an alkyl group whose carbon number ranges from 1 to 4 inclusive.
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- ADDITION DE L'ACIDE THIOCYANIQUE AUX ACETYLENIQUES A L'AIDE DE Hg(II)-I. ADDITION DU GROUPEMENT SCN(1-) EN PRESENCE D'UN ACIDE FORT
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Mercury(II) thiocyanate Hg(SCN)2 catalyses thiocyanic acid HSCN addition to unactivated acetylenic compounds R1-CC-R2.Bonding of the SCN moiety to carbon occurs through sulphur or nitrogen depending upon the influence of R1 and R2; vinyl thiocyanates NCS-C(R1)=CH2 are obtained specifically from terminal acetylenic compounds but some symmetrically disubstituted alkynes may afford vinyl isothiocyanates SCN-C(R1)=CH-R2 ( R1=R2=Et, n-Bu ).A simple preparation of tetraphenylphosphonium hydrogen dithiocyanate Ph4P(1+)*(1-) is reported.
- Giffard, Michel,Cousseau, Jack,Gouin, Lucien,Crahe, Marie-Renee
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p. 801 - 810
(2007/10/02)
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