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21.
Gökce H Bahçeli S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1783-1793
The molecular geometry, vibrational frequencies, 1H and 13C NMR chemical shifts, UV-vis spectra, HOMO-LUMO analyses, molecular electrostatic potentials (MEPs), , thermodynamic properties and atomic charges of 3- and 4-Nitrobenzaldehyde oxime (C7H6N2O3) molecules have been investigated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with the 6-311++G(d, p) basis set. The calculated optimized geometric parameters (bond lengths and bond angles), the vibrational frequencies calculated and 13C and 1H NMR chemical shifts values for the mentioned compounds are in a very good agreement with the experimental data. Furthermore, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) have been simulated and the transition states, energy band gaps and molecular electrostatic potential (MEP) maps for each oxime compound have been determined. Additionally, we also report the infrared intensities and Raman activities for the compounds under study. 相似文献
22.
A novel-modified electrode has been developed, by electrodeposition of palladium nanoparticles (PdNps) on polypyroline film-coated (Poly(Pr)) graphite electrode. The modified electrode (PdNps/Poly(Pr)/GE) was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) techniques. SEM proved that the palladium nanoparticles were uniform distributed with an average particle diameter of 20–45 nm. A higher catalytic activity was obtained for curcumin oxidation using this new modified electrode (PdNps/Poly(Pr)/GE). The square wave voltammogram of curcumin in pH 2 phosphate buffer exhibited an anodic peak at 0.504 V. This oxidation peak current was found to be linearly related to curcumin concentrations in the ranges of 5.0?×?10?9 to 1.0?×?10?7 M with a detection limit of 1.2?×?10?9 M. This novel-modified electrode showed excellent sensitivity, compared with the existing reports about determination of curcumin. 相似文献
23.
The FT-IR and micro-Raman spectra of three n-alkyltrimethylammonium bromides (dodecyltrimethylammonium bromide (DTAB), tetradecyltrimethylammonium bromide (TTAB) and hexadecyl(cetyl)trimethylammonium bromide (CTAB)) in powder form were recorded in the regions 4000–550 cm?1 and 3200–300 cm?1, respectively. The optimized geometries and vibrational frequencies of DTAB, TTAB and CTAB have been carried out with ab initio Hartree-Fock (HF) and density functional theory method B3LYP calculations with the 6–31 G (d, p) basis set in the ground state. The comparison of the observed fundamental vibrational frequencies and calculated results for the fundamental vibrational frequencies of DTAB, TTAB and CTAB indicate that the scaled B3LYP method is superior compared to the scaled HF method. 相似文献
24.
Using a complete set of 2H-labeled isotopomers, the gas-phase reactions of Ti+ to Zn+ with butyl isothio-cyanate are studied. The main product for most of the metal ions is MHNCS+ formed by an ion/dipole mechanism. Exceptions are Cr+, which yields significant amounts of H2 and H2S loss, Mn+, which is the only ion that does not form MHNCS+ at all but produces mainly C2H4 and C3H6, and Zn+, which predominantly reacts by charge transfer. 相似文献
25.
Semiha akr Ender Bier Katsuyuki Aoki Emine Cokun 《Crystal Research and Technology》2006,41(3):314-320
A new nicotinamide complex of Fe(II) cation was prepared by reaction between ferrous sulfate and nicotinamide in aqueous solution. The complex was characterized on the basis of elemental analysis, FT IR and UV–VIS spectroscopy, electrochemistry (cyclic voltammetry) and X–ray crystallography. The complex consists of the molecular composition of [Fe(nicotinamide)2(H2O)4]· [Fe(H2O)6]·(SO4)2·2H2O. The complex crystallizes in the monoclinic space group P 21/c [a = 12.862(3), b = 7.110(3), c = 16.382(3) Å; β = 95.79(2)°]. It has been proven that nicotinamide is coordinated to Fe(II) through the nitrogen atom of its heterocyclic ring. © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
26.
Pan
e Naumov Gligor Jovanovski Mirjana Ristova Ibrahim Abdul Razak Semiha kir Suchada Chantrapromma Hoong‐Kun Fun Seik Weng Ng 《无机化学与普通化学杂志》2002,628(13):2930-2939
Four different coordination patterns were observed following the partial or complete thermodynamically‐controlled ligand substitution of the hydrated tetraaquabis(o‐sulfobenzimidato‐N)copper(II) complex with heterocyclic bases as examined by X‐ray diffraction. The N‐heterocycle directs the o‐sulfobenzimidate (saccharinate) anion into the immediate coordination polyhedron of the metal by any of the imido, carbonyl or sulfonyl functionalities, or as a lattice counter‐ion in the crystal lattice. Aqua(o‐sulfobenzimidato‐O)tetrakis(4‐methylpyridine)copper(II) o‐sulfobenzimidate hemihydrate ( 1 ) crystallizes in the monoclinic space group P21/n [a = 14.7858(2), b = 16.9090(1), c = 26.2350(2)Å; β = 92.861(1)°], aquadi(o‐sulfobenzimidato‐N)bis(4‐propylpyridine)copper(II) ( 2 ) in the tetragonal space group P42/n [a = 15.4127(1), c = 13.4604(1)Å], diaquatetrakis(3‐(2‐propenyl)imidazole)copper(II) di‐o‐sulfobenzimidate ( 3b ) in the monoclinic space group P21/c [a = 9.3959(5), b = 28.029(2), c = 8.8763(3)Å; β = 111.175(1)°] and di(o‐sulfobenzimidato)tetra(isoquinoline)copper(II) ( 4b ) in the orthorhombic space group Pna21 [a = 23.2132(6), b = 11.5760(2), c = 17.6297(4)Å]. The copper atom in 1 is six‐coordinate in a distorted trans‐N4O2Cu octahedron with elongated copper—oxygen bonds [Cu—Owater = 2.462(3), Cu—Osulfonyl = 2.567(3)Å]. This adduct represents the first example of a combined Osulfonyl/ionic coordination of the o‐sulfobenzimidate ion in the same crystal. The copper atom in 2 is five‐coordinate in the form of a N4OCu square pyramid [Cu—Owater = 2.238(5)Å]. In 3 , the o‐sulfobenzimidate anions are linked to the copper atom through the coordinated water molecule forming a distorted octahedral N4O2Cu environment. In 4 , the copper atom is nearly octahedrally coordinated by four nitrogen atoms and a pair of o‐sulfobenzimidate carbonyl oxygen atoms. The structural details of the o‐sulfobenzimidate coordination pattern correspond well with the 298 and 77 K FT IR spectra of the adducts. The structures of two other solid adducts, tris(3‐(2‐propenyl)imidazole)copper(II) di‐o‐sulfobenzimidate trihydrate ( 3a ) and diaquabis(o‐sulfobenzimidato‐N)bis(isoquinoline)copper(II) ( 4a ) have been predicted by their spectral features. Alteration of the o‐sulfobenzimidate coordination mode upon changing the heterocycle ligand shows that this moiety is as a convenient polyfunctional structural tool for the construction of functional solids. 相似文献
27.
Bare Fe(I) cations act in the gas phase as dehydrosulfurization catalysts for butyl isothiocyanate by specifically coupling the S-atom with remote H-atoms from the ω and (ω ? l) position of the alkyl chain. Other losses induced by Fe(I) are due to ‘remote functionalization’, the formation of ion/dipole intermediates, and insertion/β-hydrogen shift processes. 相似文献