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1.
E. A. Evsei V. R. Pupkevich A. M. Kirillov E. A. Telushchenko M. N. Kopylovich A. K. Baev 《Journal of Applied Spectroscopy》2001,68(5):736-742
A range of coprecipitated Fe(III)-Me(II) (Me(II) = Ni, Cu) hydroxides and of the products of their thermolysis have been investigated by the IR spectroscopy method. The basic absorption bands has been assigned, and the chemistry of the process of formation of coprecipitated hydroxides has been discussed from the standpoint of generation of heteronuclear hydrococomplexes. 相似文献
2.
Abstract Abstract: The vibrational spectra of crystalline anhydrous copper (II) propionate and butyrate were studied by FT-IR spectroscopy. A detailed assignment of the spectra of both compounds is presented and discussed. It is shown that the presence of two non-equivalent sets of carboxylate ligands within the crystals gives rise to several band splittings, which are particularly evident in those bands ascribable to normal modes involving predominantly the -CβH3 or -CβH2-fragments. In addition, the vibrational assignments made for the studied molecules are shown to be very useful to help understanding the much more complex spectra of long chain copper carboxylates. 相似文献
3.
The new complexes CuX2(LH2), CuX2 (SH3) (X = Cl, Br), CuX(LH2), CuX(SH3) (X = Cl, Br, I), CuX(H4MTO)2 (X = Cl, Br), Cul(H4MTO) and CuX(H3MMTO)2 (X = Cl, Br, I), where LH2 = N.N′-dimethyl-monothiooxamide, SH3 = N(s)-methylmonothiooxamide, H4MTO = monothiooxamide and H3MMTO = N(o)-methylmonothiooxamide, have been prepared. The complexes were characterized by elemental analyses, conductivity measurements, magnetic moments and spectroscopic (UV/VIS, FT-IR, Laser-Raman) studies. The vibrational analysis of the complexes has been given using NH/ND, CH3/CD3 and 63cu/65cu isotopic substitutions. The neutral monothiooxamides behave as monodentate ligands in the Cu(I) complexes coordinating through their thioamide sulfur atom. The ligands LH2 and SH3 act as bidentate chelating agents in the Cu(II) complexes with ligated atoms being the thioamide sulfur and the amide oxygen. 相似文献
4.
We report here the low temperature emission spectra in the heterometal dinuclear 3d-4f assembled molecular system [(acac)2CrIII(μ-ox)LnIII(HBpz3)2] (Cr(ox)Ln:acac−=acetylacetonate, ox2−=oxalate, HBpz3−=hydrotris(pyrazol-1-yl)borate; Ln=La, Nd, Ho, Er , Tm and Yb) in comparison with those of Na[Cr(acac)2(ox)] and [(HBpz3)2Ln(μ-ox)Ln(HBpz3)2](Ln=Nd and Er). From 10 to 150 K the Cr(ox)Ln complexes show a broad emission band around 800 nm from the 2E state of Cr(III) moiety. At room temperature no 2E-4A2 emission was observed in the Cr(ox)Ln except for the La and Lu complexes. On warming from 10 to 300 K rapid quenching of the 2E-4A2 emission of Cr(III) is suggested to result from the energy transfer from Cr to Ln in the Cr(ox)Ln. The excitation spectra and the life-time were also measured with monitoring the 4f-4f emission peaks of the Cr(ox)Yb complex. 相似文献
5.
《光谱学快报》2013,46(5):629-638
The chelates of Cu(II) ion with some quinoxalinone compounds have been prepared and characterized by elemental analysis, IR, UV-Vis, magnetic susceptibility and TGA. It is shown that the ligands behave as bi- or tridentate ligands with the coordination of one or two chloride atoms in most of the complexes. The thermal decomposition of the compounds has been used to confirm structural information. 相似文献
6.
Tetranuclear europium(III) complexes, [Eu4(μ-O)(L1)10] (L1=2-hydroxy-4-octyloxybenzophenone,1) and [Eu4(μ-O)(L2)10] (L2=2-hydroxy-4-dodecyloxybenzophenone,2) were synthesized by the reaction of lanthanide nitrates with L1 or L2 in the presence of triethylamine in methanol. The photosensitized emission bands of the both Eu(III) complexes in THF-d8 were observed around 579, 590, 615, 653, and 699 nm by the excitation of the ligands at 380 nm, whereas the emission from the mononuclear complex 3 containing ethanol molecules was almost quenched. The emission efficiencies were determined to be 3.1±0.1% for 1 and 3.9±0.1% for 2, respectively. The differential scanning calorimetry (DSC) measurements demonstrated that the decomposition points of 1 and 2 were 309 °C and 320 °C, respectively, indicating high thermostability of these complexes compared to the mononuclear Eu(III) complex 3 (250 °C). New strategy for designing stable rare earth compounds giving strong emission would be emphasized by introducing polynuclear complexes. Polynuclear complexes should open a wide range of molecular design for photosensitized luminescence and thermal stability. 相似文献
7.
Nidal A. Zatar Ali Z. Abu-zuhri Mohammad A. Al-nuri Foad M. Mahmoud Ahmad A. Abu-Obaid 《光谱学快报》2013,46(9):1203-1214
A method for simultaneous spectrophotometric determination of total iron, iron(II) and iron(III) in mixtures containing other metal ions has been described. The method is based on the complexation of iron with di-2-pyridyl ketone benzoylhydrazone (DPKBH) in 50% (v/v) ethanolic solution. Iron(II) complex with DPKBH exhibits two absorption maxima at 360 and 650 nm. meanwhile iron(II1) complex with DPKBH exhibits only one maximum at 360nm. Iron(II) and iron(III) complexes with DPKBH have similar behaviour at 360nm. Iron forms 1:2 complexes with the reagent. Beer's laws are obeyed over the ranges 0.1–2 μgml-1 and 0.4–5 μgrn1-l for iron(II) complexes at 360 and 650nm respectively. Iron(III) showed results similar to those obtained for iron(II) at 360nm. The effect of pH, effect of excess reagent. the stability of complexes. and the tolerance limit of many metal ions have been reported. The method is applied to the determination of total iron, iron(I1). and iron(II1) in synthetic solutions. 相似文献
8.
The crystal and molecular structure of (L-proline-L-alanine) Cu·2·5 H2O has been determined by the heavy atom method with 583 visually estimated reflexions and refined by full matrix least squares toR=0·101. The crystals are monoclinic witha=16·47 (3),b=7·74 (2),c=9·51 (3) Å andβ=109·7 (5)°; space groupC2;Z=4. The copper coordination is nearly square pyramidal with one water in the basal plane and another occupying the apical together with the aminoN, peptideN and the carboxylO of the dipeptide in the coordination. The Cu-peptide-Cu linkage isvia the hydrogen bonding between the water in the basal plane and the carbonyl O atom of the proline residue. One water is on the 2-fold axis. 相似文献
9.
建立了流动注射(FI)编结反应器(KR)在线预富集与火焰原子吸收光谱(FAAS)联用非分离状态下测定铁的价态的新方法。进样流速6.0 mL.min-1;进样时间60s,测定0.04 mg.L-1的Fe(Ⅲ)和Fe(Ⅱ),Fe(Ⅲ)和Fe(Ⅱ)的浓集系数(EF)分别为41和9;检出限分别为2.5和14.3μg.L-1;相对标准偏差(RSD,n=11)分别为2.3%和3.1%。以0.1‰φ的三乙醇胺为掩蔽剂,Fe(Ⅲ)和Fe(Ⅱ)在水样中的回收率分别为97%~101%和96%~100%。 相似文献
10.
The infrared spectra of trans-Cs2[CrCl2 (H2O)4Cl3 and its deuterated isotopomers were investigated at room and liquid nitrogen temperature and at intermediate temperatures as well. The spectra of the partly deuterated analogues are not in agreement with the crystallographic data [1], perhaps because of the incorrect choice of the space group in which the structure was solved and refined or the presence of disorder in the structure. 相似文献
11.
The new complexes trans-[PdX2(H4MTO)2] (X = Cl, Br, I), trans-[PdX2(H3MMTO)2] (X = Cl, Br, I), trans-[PdX2(SH3)2] (X = Cl, Br), [Pd(H4MTO)4]CI2 and [Pd(H3MMTO)4]CI2, where H4MTO = monothiooxamide, H3MMTO = N(o)-methylmonothiooxamide and SH3 = N(s)-methylmonothiooxamide, have been prepared. The complexes were characterized by elemental analyses, conductivity measurements, X-ray powder patterns, thermal methods and spectroscopic (UV/VIS, FT-IR, Laser-Raman) studies. The vibrational analysis of the complexes is given using NH/ND and CH3/CD3 isotopic substitutions. Monomeric square planar structures are assigned for the complexes in the solid state. The neutral monothiooxamides behave as monodentate ligands coordinating through their thioamide sulfur atom. The complex [Pd(SH2)2] was isolated during the thermal decomposition of trans-[PdCl2(SH3)2]. 相似文献
12.
We present the results from investigations of the nonlinear refractive index and nonlinear absorption coefficient of tris(acetylacetonato)manganese(III) solution, using Z-scan technique with a low-power continuous-wave laser at 514 nm. We demonstrate that the light-induced nonlinear refractive index variation leads to strong self-focusing and self-defocusing. A pump and probe technique was used to investigate the cause of nonlinearity. Furthermore, the nonlinear absorption effect was utilized to demonstrate all optical switching. 相似文献
13.
Two novel ternary rare earth perchlorate complexes had been synthesized by using bis(benzoylmethyl) sulfoxide as first ligand (L=C6H5COCH2SOCH2COC6H5), salicylic acid as second ligand (L′=C6H4OHCOO−). The compounds were characterized by elemental analysis, TG-DSC and molar conductivities in DMF solution. The composition was suggested as [REL5L′](ClO4)2·nH2O (RE=Tb, Dy; n=6, 8 ). Based on IR, 1HNMR and UV spectra, it showed that the first ligand, bis(benzoylmethyl) sulfoxide (L), bonded with Tb(III), Dy(III) ions by the oxygen atom of sulfinyl group. The second ligand, salicylic acid group (L′), not only bonded with RE(III) ions by one oxygen atom of carboxyl group but also bonded with RE(III) ions by oxygen atom of phenolic hydroxyl group. In bis(benzoylmethyl) sulfoxide system, fluorescent spectra of the complexes showed that the luminescence of Tb(III), Dy(III) ions was enhanced by the second ligand salicylic acid. The ternary complexes had stronger fluorescence than the binary ones where only bis(benzoylmethyl) sulfoxide acted as ligand. Phosphorescent spectra of the two ligands indicated that the coordination of salicylic acid resulted in the matching extent increasing between the triplet state of ligand and excited state of the rare earths. The relationship between fluorescence lifetime and fluorescence intensity was also discussed. 相似文献
14.
Both reductive and oxidatlve mode of metabolism have been hypothesized for the antitumor agent mitoxantrone. This work aims to better understand the redox properties of mitoxantrone in the presence of the physiological redox couple, copper(I)/copper(II), by means of polarograpy and spectrophotometry. The first quasi-reversible one-electron reduction of mitoxantrone to the semiquinone and the second reduction to the hydroquinone have been shown to be considerably affected by copper. Visible spectra of mitoxantrone-copper mixtures in nitrogen and oxygen purged solutions taken in a one-week period exhibit varying degrees of complexation and oxido-reduction. When copper(II), neocuprolne and mitoxantrone are mixed in a certain ratio in pH 7. 4 phosphate buffer solution, two new peaks at 584 and 632 nm emerge in the spectra indicating a ternary charge transfer complex. The complex atoichiometry was established as Cu(IT): neocuproine: tritoxan-trone = 2:4:1 by Job's method of continuous variations. The ternary complex is sensitive to the relative concentrations of mitoxantrone and copper(II), an excess of the latter giving rise to complete red ox products. This complex may be important in modeling the drug's oxidative mode of ant tumor action. 相似文献
15.
S. Balasubramanian 《Journal of luminescence》2004,106(1):69-76
Macrocylic dicarbinolamine nickel (II) complexes with diimine moiety in their ligand exhibited luminescence, when irradiated at their charge transfer band. The Stern-Volmer (S-V) plots of one of the complexes in DMF medium exhibited positive curvature, when FeC13 was used as a quencher, while the same complex showed negative curvature when nitrobenzene was used as a quencher. The mechanism for the luminescence quenching of the macrocyclic complex has also been discussed. 相似文献
16.
E. Ghomashchi 《光谱学快报》2013,46(6):849-860
Abstract Power electron paramagnetic resonance spectrum of the trinuclear complex Cu3L3 (OM)X2, xH20 (L=pyridine-2-carbaldehyde oxime, X=1/2 S042?, x=16.3) was recorded in the X-band region and interpreted in terms of a quarte (S=3/2) spin system. Vibrational studies of the complex has also been undertaken and an assignment was made of the bands observed it the low frequency infrared and Raman spectra. It was shown that the central metallic core has a C3v syametry. Theoretical calculations of the frequencies of the vibrations related to this skeleton were performed and the results are it agreement with the experimental data. 相似文献
17.
The pentadentate ligands 3-OH-5L?=?[N,N′-Bis(1,3-dihydroxy-2-benzylidene)-1,7-diamino-4-azaheptane] and 4-OH-5L?=?[N,N′-Bis(1,4-dihydroxy-2-benzylidene)-1,7-diamino-4-azaheptane] has been prepared by a Schiff base condensation between 1,7-diamino-4-azaheptane and the dihydroxybenzaldehyde. Complexation with Fe(III) yields high-spin (S?=?5/2) complexes of [FeIII(3-OH-5L)Cl] and [FeIII(4-OH-5L)Cl]. These precursors were combined with [M(CN) x ] y? (M?=?W(IV), Mo(IV), Ru(II), Co(III)) and heptanuclear and nonanuclear clusters of [M{(CN-FeIII(3-OH-5L)} x ]Cl y and [M{(CN-FeIII(4-OH-5L)} x ]Cl y resulted. Such starshaped hepta- and nonanuclear compounds are high-spin systems at room temperature. On cooling to 10 K some of the iron(III) centers switch to a second high-spin state as proven by Mössbauer spectra, i.e. multiple electronic transitions. Parts of the compounds perform a high-spin to high-spin transition. 相似文献
18.
It has recently been shown that the 2,2,6,6-tetra-methylheptane-3,5-dione (tmhd) complexes of a number of lanthanide ions possess the useful property of inducing large chemical shifts in the proton NMR spectra of certain compounds containing OH or other nucleophilic groups1–8. The resulting spectra are frequently more readily assignable and analysable. Although europium and praseodymium appear to be the most suitable ions for such studies, the shifting effect is also observed with other lanthanide ions.5,6 相似文献
19.
Abstract Rh(II) complexes are rather scarce1 and often form dimeric structures, which are diamagnetic. The ESR spectra of definite Rh(II) species have so far been claimed for Rh in ZnWO3 2, [Rh S4C4(CN)4]2 ?, 3′4 [Rh(π-C5H5)2]5, [(π-C5H5)Rh(π-C2H4)2]+6, and an irradiation produced [RhCπ2(CN)4]2 ? complex.7 A detailed analysis has been performed on the first2, the second4 and the last7 complexes. The first system shows an almost axial symmetry and the unpaired electron has been assigned to the dxy orbital2 (the x,y,z axes are defined along the octahedral metal-ligand directions). The sulfur ligand complex and the dichlorotetracyano system have their unpaired electron in the dZ 2 orbital. 4,7 In the course of studies 8-10 on oxygenation of a Rh(I) complex, [RhCπ(C8H14)2]2, we observed 10 that a well defined ESR spectrum develops during the reaction in N,N′-dimethylacetamide (DMA) - lithium chloride media. For experimental detail, reference 10 should be consulted. The data summarized in the table refer to the spectrum B in that reference and are attributed to a Rh(II) species. 相似文献
20.
The infrared spectra of the hydrates of inuline oligomers and the complex of iron(III) with inuline oligomers and their partial deuterated analogs were studied. From the appearance and frequencies of the bands in the range of OH and OD vibrations it was concluded that these crystalohydrates have one type of H2O molecule, and relatively weak hydrogen bond (estimated Ow…O distances are 280 and 283 pm for inuline and its complex, respectively). From the FTIR spectra of the complex the β2-form for iron(III) oxihydroxide (FeOOH) was determined. On the basis of the electron spin resonance spectra it was concluded that Fe+3 ions of octahedral configuration (g-value 2.03 ± 0.01) were present in the complex. From the measured ESR line width (ΔH = 100 ± 5 mT) the approximate Fe inter atomic distance of 0.21 nm was calculated, indicating a dense packing of Fe atoms in the cluster. 相似文献