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21.
Drozd M Baran J Pietraszko A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(13-14):2809-2821
The crystal structure of diguanidinium hydrogenarsenate monohydrate has been found to belong to the P42(1)/c space group of the tetragonal system, with Z = 8, a = 17.114(2) A, c = 7.3500(10) A. In this complex, a network of hydrogen bonds links water molecules and hydrogenarsenate ions. The hydrogenarsenate ions form hydrogen-bonded chains along the crystallographic c-axis. Detailed vibrational studies have been carried out (FTIR and FT-Raman on powder samples, polarized FTIR microscope on a small single crystal at room temperature). The vibrational spectra are discussed in relation to the crystal structure. Calorimetric (DSC) studies have been performed, but no phase transition was found in the temperature range 100-350 K. 相似文献
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Drozd M Marchewka MK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(1):6-23
The room temperature X-ray studies of L-lysine x tartaric acid complex are not unambiguous. The disorder of three atoms of carbon in L-lysine molecule is observed. These X-ray studies are ambiguous. The theoretical geometry study performed by DFT methods explain the most doubts which are connected with crystallographic measurements. The theoretical vibrational frequencies and potential energy distribution (PED) of L-lysine x tartaric acid were calculated by B3LYP method. The calculated frequencies were compared with experimental measured IR spectra. The complete assignment of the bands has been made on the basis of the calculated PED. The restricted Hartee-Fock (RHF) methods were used for calculation of the hyperpolarizability for investigated compound. The theoretical results are compared with experimental value of beta. 相似文献
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Drozd M Baran J Ratajczak H 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(3):646-668
Polarized IR and Raman spectra of single crystal were measured at room and at low temperature. The polarized IR spectra were measured by transmission and specular reflection method. The IR-microscope was used for vibrational measurement of small monocrystals. Assignment of the bands is proposed on the basis of oriented gas model approximation. The polarized vibrational spectra are discussed in relation to the crystal structure and possible proton conductivity and phase transition. 相似文献
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B. L. Tumanskii V. V. Bashilov S. P. Solodovnikov N. N. Bubnov O. G. Sinyashin I. P. Romanova V. N. Drozd V. N. Knyazev V. I. Sokolov 《Russian Chemical Bulletin》1999,48(9):1786-1788
Regioselectivity of the addition of phosphoryl radicals to the products of cycloaddition of substituted nitriloxides to fullerene
C60 was studied by ESR spectroscopy. The effect of fluorine-containing alcohols on the magnetic resonance parameters of the isomers
of spinadducts of phosphoryl radicals located at different distances from the five-membered heterocycle was studied. Complexation
of the obtained isomeric spin-adducts with (CF3(3COH leads to a 3 to 5 G increase in the constant of hyperfine interaction with the phosphorus nucleus, which makes it possible
to observe additional lines in the ESR spectrum.
Deceased.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1808–1811, September, 1999. 相似文献
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Quantitative EPR study on free radicals in the natural polyphenols interacting with metal ions and other environmental pollutants 总被引:1,自引:0,他引:1
Jezierski A Czechowski F Jerzykiewicz M Golonka I Drozd J Bylinska E Chen Y Seaward MR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(6):1293-1300
Quantitative electron paramagnetic resonance (EPR) method was applied to characterise radicals stabilised in polyphenolic matrices of various biogenic materials: lichens, mosses, composts, soils, peats, brown coals and sewage sludge sediments. The investigations were carried out on raw materials and extracted fractions of humic acids (HA). General trends of g value and spin concentration changes were found. These parameters in lichens strongly depend on lichen species and air pollution. Determination of the g value and semiquinone spin concentration allows to assess degree of transformation of organic matter in compost, soil, peat and lignite. Application of gaseous ammonia as a base penetrating the organic matrices extends the possibilities and usefulness of the method. Interaction of metal ions with humic materials is illustrated by interaction of VO2+ ion with peat and lignite HA as well as demineralised (raw and carbonised) brown coal. Our investigations demonstrate that quantitative EPR is a rapid and effective monitoring method to study the influence of various environmental factors on substances containing polyphenolic matrices. 相似文献
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