Search results for " Spectra"
showing 10 items of 709 documents
Fluoreszenz‐Untersuchungen an styrylsubstituierten Benzolen
1986
Die Fluoreszenz-Abklingzeiten der stilbenartigen Verbindungen 1 – 4 zeigen, das die mittleren Lebensdauern dieser Molekule im elektronisch angeregten Singulettzustand um rund zwei Zehnerpotenzen hoher sind als bei trans-Stilben selbst. Anhand von UV-Absorptions-und Anregungsspektren wird das auf einen neu gefundenen S1-Zustand zuruckgefuhrt, der einem verbotenen Ubergang S0 S1 auf der langwelligen Seite der intensiven Absorption entspricht. Investigations on the Fluorescence of Styryl-substituted Benzenes Fluorescence decay measurements of the stilbene-like compounds 1 – 4 demonstrate that the average lifetimes of these molecules in the electronically excited singlet state are about 102 tim…
Influence of Au, Ag, and Cu Adatoms on Optical Properties of TiO2 (110) Surface: Predictions from RT-TDDFT Calculations
2022
This study was financially supported by Flag-ERA JTC To2Dox project (S.P.) and M-ERA-NET2 project SunToChem (E.A.K.). M.G.B. thanks the support from the Program for the Foreign Experts (Grant No. W2017011) offered by Chongqing University of Posts and Telecommunications and the National Foreign Experts Program for “Belt and Road Initiative” Innovative Talent Exchange (Grant No. DL2021035001L), Estonian Research Council grant PUT PRG111, European Regional Development Fund (TK141), NCN project 2018/31/B/ST4/00924. Institute of Solid State Physics, University of Latvia, as the Center of Excellence, has received funding from the European Union’s Horizon 2020 Framework Program H2020-WIDESPREAD-01…
Complexes of diorganotin(IV) dihalides with diphosphoryl compounds and their Mössbauer spectra
1993
Synthese und Strukturen neuer Eisen-Sauerstoff-Alkoxid-Cluster
2004
Der Eisen-Sauerstoff-Alkoxy-Cluster [Fe9O3(OC2H5)21]·C2H5OH kann unter unterschiedlichen Bedingungen zu Molekulen umgesetzt werden, denen alle die allgemeine Formel [Fe5O(OR)8(OR′)5] gemeinsam ist. Erwarmt man [Fe9O3(OC2H5)21]·C2H5OH in Toluol, so entsteht [Fe5O(OC2H5)13], das durch Kristallisation abgetrennt werden kann, wohingegen ein Auflosen von [Fe9O3(OC2H5)21]·C2H5OH in tert-Butylamin zum 1 : 2-Addukt [Fe5O(OC2H5)13]·2 t-Bu-NH2 fuhrt. Mit Triethyl- oder Triphenylsilanol entsteht aus [Fe9O3(OC2H5)21]·C2H5OH wieder ein Sauerstoff-Eisencluster des gleichen Motivs: [Fe5O(OC2H5)8{OSi(C2H5)3}5] bzw. [Fe5O(OC2H5)8{OSi(C6H5)3}5]. Die Molekulstruktur [Fe5O(OC2H5)8{OSi(C2H5)3}5], die uber Rontg…
A heptanuclear Fe(II)–Fe(III)6 system with twelve unpaired electrons
2000
Abstract The pentadentate ligand 5 LH2 = saldptn = N,N′-bis(1-hydroxy-2-benzyliden)-1,7-diamino-4-azaheptane has been prepared by a Schiff base condensation between 1,7-diamino-4-azaheptane and the corresponding salicyaldehyde. Its complexation with Fe(III) gave the high-spin (S=5/2) complex of [Fe III ( 5 L)Cl]. This precursor was combined with [Fe(CN)6]4− and a blue heptanuclear complex [FeII{(CN)Fe III ( 5 L)}6]Cl2 resulted. This system belongs to the class of high-spin molecules possessing twelve unpaired electrons (S=6) as proven by the magnetic susceptibility measurements and Mossbauer spectra.
Crystal structure, magnetic properties and esr studies of (4-apyH)4[CuIIBr4] [CuIBr2]2: a novel Cu(II)⧹Cu(I) system containing bromocuprate(I) chains…
1998
Abstract The synthesis, crystal structure, ESR spectra and magnetic properties are reported for the Cu(II)⧹Cu(I) compound (4-apyH)4[Cu3Br8] (4-apyH = C5H7N2 = 4-aminopyridinium). Single-crystals of the compound were grown by slow diffusion of n-hexane on an ethanolic solution of (4-apyH)2[CuBr4] · H2O. The crystal structure is made up of organic cations, isolated [CuIIBr4]2− anions and infinite [CuIBr2]nn− chains composed of edge-sharing CuIBr4 tetrahedra. N–H · · · Br hydrogen bond interactions between organic counter cations and inorganic anionic units are present and contribute to the cohesiveness of the crystal packing. Magnetic susceptibility measurements showed a good isolation of Cu(…
Copper(II) Complexes with Derivatives of Barbiturate
1984
Abstract NaCuL2(OH).1,5H2O, KCuP2(OH).1H2O, Na2CuL4 and K2CuP4-8H2O (HL=Phenobarbitone and HP=Methyl Phenobarbitone) were prepared and characterized by elemental analysis, IR and electronic spectral data and magnetic susceptibility measurements. The ESR spectra show and octahedral environment for the Cu(II) ion.
GIAO/DFT 13C NMR Chemical Shifts of 1,3,4-Thiadiazoles
2007
1 H, 13 C and 15 N NMR spectra of 2-acetylamino-1,3,4-thiadiazole and its 5-substituted derivatives have been measured and assigned based on reference data, as well as homo- and heteronuclear 2 D NMR experiments. In addition, the GIAO/DFT approach at the B3LYP level of theory using the 6-311G basis set was used to calculate the 13 C NMR chemical shifts. Although this method gives reliable results for 2-arylhydrazones of 1,3-diphenylpropanetrione, 2-phenacylpyridines, (Z)-2-(2-hydroxy-2-phenylvinyl)pyridines, 4-fluoroanilines, (1Z,3Z)-1,4-di(pyridin-2-yl)buta-1,3-dienediols and their tautomeric forms, the calculated chemical shifts for the 1,3,4-thiadiazoles studied are less satisfactory. Pr…
Thiophen—Mangantricarbonyl-Komplexe
1967
Abstract Cationic thiophenemanganese tricabonyl complexes of the formula [C 4 (CH 3 ) x H 4- x S Mn(CO) 3 ] + have been prepared with 2-methyl-, 3-methyl-, 2,5-dimethyl-, 2,3,5-trimethyl-, tetramethylthiophene, and with thiophene by the reaction of Mn(CO) 5 Cl+AlCl 3 or AlBr 3 with the thiophenes in petrol ether, at 100–110°. The complexions give yellow solutions which are fairly stable. Their IR and some NMR spectra are given and discussed.
4-Fluoroanilines: synthesis and decomposition
2001
Abstract Fourteen N- and/or 2-substituted 4-fluoroanilines were prepared (the series includes N–C2-bridged compounds). Some of them were found to be thermally unstable when dissolved in chloroform. Both 19 F NMR spectra and comparison of GIAO-DFT calculated and experimental 13 C chemical shifts were used to suggest decomposition products of 4-fluoroanilines.