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1.
We have used electronic spectroscopy in the 160–1100 nm range to study the polyvinyl alcohol-nickel(II) chloride system. Based
on the results obtained, we hypothesize formation of mixed-ligand complexes of the type [Ni(H2O)6-nCln]2-n (n = 0, 1,..., 5) in the polyvinyl alcohol matrix. Transformation of the coordination sphere as the NiCl2 concentration changes is apparent both in the region of the d-d transition bands (350–1100 nm) and in the region of the charge
transfer bands (160–250 nm). We propose assigning the absorption bands separated by mathematical treatment to complexes of
specific compositions.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 136–138, January–February, 2006. 相似文献
2.
Xiaoyi Li Yiqun Wu Donghong Gu Fuxi Gan 《Applied Physics A: Materials Science & Processing》2011,102(3):719-724
Three novel metal(II) complexes, CoL2, NiL2 and CuL2 (L = (Z)-4-(2-(1,3-dimethyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one were
synthesized. Their structures were postulated based on elemental analyses, 1H NMR, ESI-MS, FT-IR spectra and UV-vis spectra. The effect of different central metal(II) ions on absorption bands of the
metal(II) complexes in CHCl3 solutions was researched. The result indicates that the bathochromic shift is CuL2 > NiL2 > CoL2. The absorption properties of thin films and thermal stability of these complexes are also discussed. In addition, the optical
constants (complex refractive index N=n+ik) and thickness of the complex thin films on polished single-crystal silicon substrates were measured by spectroscopic ellipsometry.
Results indicate that the metal(II) complexes would be a promising recording medium candidate for blu-ray recordable optical
storage system due to good absorption at 405 nm, high thermal stability and sharp thermal decomposition, and a high n values of 1.35–1.45 and a low k values of 0.33–0.39. 相似文献
3.
Complexation and photophysical properties of complexes of lanthanide ions, Ln(III), with diethyl(phthalimidomethyl)phosphonate ligand, DPIP, were studied. Interactions between Ln(III) and DPIP were investigated using Nd(III) absorption and Eu(III) and Tb(III) luminescence (emission and excitation) spectra, recorded in acetonitrile solution containing different counter ions (NO3-, Cl- and ClO4-). Results of the absorption spectroscopy have shown that counter ions play a significant role in the complexation of Ln(III)/DPIP complexes. Studies of luminescence spectra of Eu(III) and Tb(III) ions proved that the formation of Ln(III)/DPIP complexes of stoichiometry Ln:L=1:3 is preferred in solution. Based on the results of elemental analysis, Nd(III) absorption spectra and IR and NMR data, it was shown that the DPIP ligand binds Ln(III) ions via oxygen from phosphoryl group, forming complexes of a general formula Ln(DPIP)3(NO3)3·H2O, in which the NO3- ions are coordinated with the metal ion as bidentate ligands. Luminescent properties and energy transfer, from the ligand to Ln(III) ions in the complexes formed, were studied based on the emission and excitation spectra of Eu(III) and Tb(III). Their luminescent lifetimes and emission quantum yields were also measured. 相似文献
4.
A. Yu. Taraeva V. I. Gerasimova Yu. S. Zavorotnyi A. O. Rybaltovskii 《Journal of Applied Spectroscopy》2007,74(1):44-50
We have studied the effect of external factors (humidity, pressure, temperature) on the stability of the organometallic compound
Eu(fod)3 (fod = 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octadione) impregnated into polypropylene (PP) using supercritical
CO2. We have established that under the influence of external conditions, there is a decrease in the integrated intensity of
the absorption band for the Eu(fod)3 molecule and the photoluminescence (PL) of Eu3+ ions as a function of the properties of the medium, and in the presence of water molecules the shape of the bands for these
spectra changes. We propose a physical model explaining the behavior of the absorption and photoluminescence spectra when
the polypropylene films are stored under different conditions.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 42–47, January–February, 2007. 相似文献
5.
We present the results of a spectral study of the effect of low-intensity laser radiation on the molecular structure of blood
and blood components. Analysis of the Fourier transform IR absorption spectra of blood confirmed the changes we observed previously
in the oxygen transport characteristics of blood with intravenous exposure to the emission from a He-Ne laser. We show that
structural and conformational changes in the hemoglobin tetramer, initiated by laser-induced photoreactions between Hb and
oxygen, lead to characteristic changes in the shape and intensity of the IR bands for NH stretching vibrations, and also the
amide I and amide II absorption bands. In the IR spectra of irradiated blood samples, we note increased absorption in the
bands for stretching vibrations of the phosphate groups (945–1280 cm−1), which is evidence for an increase in the nucleic acid content (DNA, RNA). In the spectra of plasma and erythrocytes prepared
from irradiated blood, there are no changes in this region of the IR spectrum. At the same time, in the IR spectra of samples
of irradiated plasma, the intensity of the bands for stretching vibrations of the CH2 groups increases substantially.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 106–112, January–February, 2006. 相似文献
6.
N. M. Shishlov Sh. S. Akhmetzyanov S. L. Khursan 《Russian Journal of Physical Chemistry B, Focus on Physics》2010,4(5):846-859
IR spectroscopy measurements show that films of poly(diphenyl sulfophthalide) (PDSP), a cardo polymer, interact with atmospheric
moisture during storage at room conditions. A total of 15 absorption bands were isolated in spectra of PDSP hydrated during
storage, which belong to sorbed water and hydrolysis products. A number of absorption bands (within 1500–1800 cm−1 and 980–1100 cm−1) were obtained by subtracting the spectrum of the film after heating from that of the initial hydrated film. At least six
individual bands in the region of the O-H bond stretching vibration were isolated by decomposing a broad complex band (3700–2000
cm−1) into Gaussian components. The isolated bands were tentatively assigned based on the available literature data and quantum-chemical
calculations of the characteristics of a number of complexes of a diphenyl sulfophthalide model compound with water molecules.
The IR spectra and energies of the hydrogen bonds formed were calculated at the B3LYP/6-311G(d, p) level. In particular, the absorption bands at 1010 and 1079 cm−1 were assigned to the symmetric stretching vibrations of the S=O bonds in the −SO3− anion, the 1062-cm−1 absorption band, to ν(C-OH), and the absorption bands at 3646, 3586, and 3475 cm−1, to complexes of water with sulfophthalide cycles of the polymer. After a long storage, PDSP largely transforms into a polymeric
oxonium salt, and its spectrum becomes similar to that of a polymeric salt prepared by alkaline hydrolysis. A general mechanism
of the interaction of PDSP with water is proposed, according to which the hydrolysis of the sulfophthalide cycles (SPC) by
sorbed water yields new hydrophilic groups, sulfoacid, and hydroxyl groups. A further sorption of water by the sulfoacid results
in its ionization and the formation of various hydroxonium forms. Sorption and hydrolysis are reversible processes: water
is desorbed and the SPC is recovered when the polymer is heated to 100–150°C, as can be judged from an increase in the intensity
of the S=O bond vibrations of the sulfophthalide cycle at 1352 and 1192 cm−1. The possibility of using strongly hydrated PDSP for manufacturing proton-conducting membranes is discussed. 相似文献
7.
L. F. Bakhturova V. V. Bakovets T. M. Levashova I. P. Dolgovesova V. O. Borisov 《Journal of Applied Spectroscopy》2000,67(1):40-44
IR absorption spectra of an intracomplex chelate compound of Cu(II) bis-dipivaloylmethanate in the spectral range 4000–300
cm−1 are investigated. A comparison is made between the spectra of the complex in different aggregative states: as a solution
in heptane and as condensed films. The molar extinction coefficients of absorption bands are calculated. The extinction coefficients
found are used to evaluate the thickness of Cu(dpm)2 films.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 1, pp. 34–37, January–February, 2000. 相似文献
8.
Yu. V. Zorenko R. M. Turchak T. I. Voznyak A. P. Luchechko 《Journal of Applied Spectroscopy》2006,73(2):211-215
By liquid-phase epitaxy from an aqueous alcoholic solution, we have obtained films of the well-known storage phospor CsBr:Eu,
and we have studied their cathodoluminescence and photoluminescence (PL) spectra compared with the undoped CsBr films. We
have established that the structure of the photoluminescence centers of the CsBr:Eu films when excited by laser radiation
in the absorption band of the Eu2+ ions (λ = 337 nm) includes Eu2+-VCs isolated dipole centers and CsEuBr3 aggregate centers, and also luminescence centers based on inclusions of hydroxyl group OH− with the corresponding emission bands in the 440 nm, 520 nm, and 600 nm regions. We have studied the dependence of the spectra
and the intensity of the photoluminescence for CsBr:Eu films on annealing temperature in air at 423–483 K, compared with analogous
dependences for CsBr:Eu single crystals obtained from the melt. We have shown that annealing the films at T = 423–463 K leads
to rapid formation of CsEuBr3 aggregate luminescence centers, while for T > 473 K thermal degradation of these centers occurs.
We conclude that the observed differences between the photoluminescence spectra of CsBr:Eu films and CsBr:Eu single crystals
may be due to additional doping of the films with OH− ions.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 191–194, March–April, 2006. 相似文献
9.
A. P. Zazhogin 《Journal of Applied Spectroscopy》1999,66(3):455-457
On the basis of analysis of relationships relating, among themselves, the positions of bands in the spectra of electron and
IR absorption of uranyl complexes in solutions and the donor ability of neutral ligands, the possibility is shown for fine-tuning
frequencies of absorption of complexes to frequencies of argon- and CO2-laser generation lines and using them in the development of methods of control over chemical reactions involving actinides.
Belarusian State University, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 66, No. 3, pp. 420–422, May–June, 1999. 相似文献
10.
1-(4-Aminoantipyrine)-3-tosylurea (H2L) and its three lanthanide (III) complexes, M(H2L)3 3NO3 [where M = Nd(III), Sm(III) and Eu(III)], have been synthesized and characterized. In addition, the DNA-binding properties
of the three complexes have been investigated by UV–vis (ultraviolet and visible) absorption spectroscopy, fluorescence spectroscopy,
circular dichroism (CD) spectroscopy, cyclic voltammetry, and viscosity measurements. Results suggest that the three complexes
bind to DNA via a groove binding mode. Furthermore, the antioxidant activity (superoxide and hydroxyl radical) of the metal
complexes was determined by using spectrophotometer methods in vitro. These complexes were found to possess potent antioxidant
activity and be better than standard antioxidants like vitamin C and mannitol.
Absorption spectra of the complex 3 inTris-HCl buffer upon addition of calf-thymus DNA. [complex]=1×10-5 M, [DNA]=(0-1) ×10-5 M. Arrow shows the absorbance changing upon increasing DNA concentrations. Inset: plots of [DNA]/(εa – εf) versus [DNA] for the titration of DNA with the complex. 相似文献
11.
Films of Mn1−x
Fe
x
Se (x = 0–0.45) solid solutions were flash-sputtered. We measured the transmission spectra of the films in the wavelength
range 200–1000 nm at room temperature. From these spectra, we calculated the absorption coefficients and determined the fundamental
absorption edge, the position of which is shifted from 2.65 eV in MnSe to 2.30 eV in solid solutions of compositions x = 0.20–0.45.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 136–138, January–February, 2007. 相似文献
12.
The structure and spectral properties of two organic ruthenium complexes used as sensitizing dyes for solar batteries (well-known
N3 dye and its selenophene-conjugated analogue C105 ([Ru(bpy)(bpysef)(COOH)2(NCS)2] (bpy = 2,2′-bipyridine, bpysef = 4,4′-bis(5-hexylselenophene-2-yl)2,2′-bipyridine)) are comparatively studied within the
density functional method. It is shown that the conjugation of the bipyridine ligand with selenophene affects the electronic
structure of the C105 dye. A multilevel model for interpreting the electronic spectra of dyes is proposed based on the analysis
of the shapes of molecular orbitals. The nature of the absorption bands of these ruthenium complexes in the region of 300–800
nm is explained. It is found that, in the polar acetonitrile solvent, these dyes are negatively solvatochromic, which agrees
with the current classical views on the effect of the solvent on the shape of electronic absorption spectra of related compounds. 相似文献
13.
Novel poly(oxyethylene phosphate) tris(β-diketonate) europium (III) complexes have been synthesized by an improved procedure
using the Atherton–Todd reaction conditions. N-ethyldiisopropylamine has been used as a mild base and propylene oxide as an
acid scavenger in order to obtain poly(oxyethylene phosphate) in yield and purity higher than those achieved by conventional
methods. The compounds have been characterized by 1H, 13C, and 31P NMR and FTIR techniques. Their absorption, fluorescent excitation and emission spectra of chloroform and abs. ethanol solutions
have been recorded and studied. The luminescent quantum yields and decay times have been determined and a dependence on the
length of the oxyethylene spacer between phosphate groups has been established. The new polymer complexes are water soluble
and have increased luminescence decay time in comparison with corresponding ternary complexes. 相似文献
14.
Experimental absorption spectra of benzene, isooctane, and their mixtures are obtained in the wavelength range λ = 1620–1820
nm in which the first overtones of vibrational frequencies of CH, CH2, and CH3 hydrocarbon groups are located. Positions of fundamental absorption bands of benzene are refined. Absorption spectra of benzene-isooctane
mixtures are shown to intersect in a narrow area near λ ≈ 1695 nm. The main maximum of benzene absorption at λ = 1671.5 ±
0.5 nm, where the influence of isooctane absorption is practically absent, is proposed for determining the content of benzene
in benzene-isooctane mixtures. A linear calibration curve for λ = 1671.5 nm that encompasses the full range of benzene concentrations
(0–100%) is presented.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 631–634, September–October, 2008. 相似文献
15.
Studies on speciation have been done in the mixtures of mixed ligand copper complexes. Three heterogeneous mixtures have been studied, each having one Cu(I) complex and one Cu(II) complex. The Cu(I) complex is [Cu(thu)Cl 0.5H2O] (1) and the Cu(II) complexes are [Cu(L-phen)(bpy) H2O] (2), [Cu(L-tyr)(phn) 2.5H2O] (3), and [Cu(dien)(ina) 4H2O.1/2SO4] (4) (where thu = thiourea, phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine, tyr = tyrosine, dien = diethylenetriamine, and ina = isonicotinate anion). The mixtures have been prepared by mixing the Cu(I) complex with each of the Cu(II) complexes in the ratio of 1:1 by mole percentage. The X-ray absorption fine structure (XAFS) spectra have been recorded at the K-edge of copper in the mixtures as well as in the complexes, separately. The aim of the present work is to make a study of the different methods of speciation using XAFS, viz., principal component analysis (PCA) and the target transformation (TT) method, the linear combination fitting (LCF) method, derivative spectra methods, and normalized difference absorption edge spectra (NDAES) analysis. It has been shown that these methods can be used to determine the relative quantity of the mixed ligand complexes in their mixtures. 相似文献
16.
In this paper, we report the synthesis of four diimine ligands incorporated with an electron donor/acceptor, as well as their corresponding Cu(I) complexes with bis(2-(diphenylphosphanyl)phenyl) ether as an ancillary ligand, resulting in four phosphorescent Cu(I) complexes. Their crystal structures as well as photophysical and thermal properties are discussed in detail. Experimental data and theoretical calculations confirm that electron donor moieties and limited conjugation system may self-restrict geometry relaxation in excited states, leading to narrowed and blue-shifted emission bands. On the other hand, electron acceptor moieties and large coplanar conjugation system are ineffective in restricting geometry relaxation, leading to broadened and red-shifted emission bands. However, the introduction of electron donors compromises thermal stability of Cu(I) complexes. We also explore one of the Cu(I) complexes as a dopant for electroluminescence application, and a maximum luminance of 680 cd/m2 peaking at 620 nm is achieved. 相似文献
17.
Haowen Huang Chunhui Li Caiting Qu Shaowen Huang Fang Liu Yunlong Zeng 《Journal of nanoparticle research》2012,14(3):754
In this article, a type of core–shell nanostructure, Au2S/AuAgS/Ag3AuS2-coated gold nanorods (GNRs) with unique optical properties was used as a sensing platform to detect fish sperm DNA (fsDNA).
The prepared core–shell nanorods are positively charged due to the adsorption of the positively charged cetyltrimethylammonium
bromide (CTAB) cations on their surface. fsDNA can form ternary fsDNA–CTAB–nanorod complexes together with CTAB and nanorod,
which provides a useful platform to detect fsDNA through absorption spectra and resonance light scattering (RLS) spectroscopy.
In this sensitive core–shell nanorod sensor, CTAB concentration and the nanoparticle dosage play important roles and have
been investigated. Moreover, the fsDNA–CTAB–nanorod complexes induce a great enhancement of RLS intensity of the core–shell
GNRs and directly proportional to the concentration of fsDNA, reaching a detection limit of about 10−9 mg/mL. This study will be significant for as-prepared core–shell GNRs for future application in biological systems. 相似文献
18.
We have found that it is possible to enhance the luminescence of Pr(III) in solutions of complexes with β-diketones: acetylacetone
derivatives containing fluoroalkyl substituents of different lengths and structures. We have established that in the presence
of organic solvents, second (additional) ligands, and surfactants shielding the central ion from the quenching effect of the
water molecules (OH oscillators), the intensity of luminescence for Pr(III) increases by a factor of 65, 38, and 45 respectively.
In this case, cationic surfactants form ionic associates with Pr(III) β-diketonates, with incorporation of one more β-diketone
molecule (ratio Pr:β-diketonate:surfactant = 1:4:1). As a result of suppression of intramolecular energy losses in solutions
of Pr(III) β-diketonates, it is possible to observe its rather intense luminescence at 605 nm (the transition 1D2 → 3H4), 612 nm (3P0 → 3H6), and 646 nm (3P0 → 3F2).
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 746–750, November–December, 2006. 相似文献
19.
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
20.
N. A. Borisevich D. K. Buslov V. N. Zhabinskii V. A. Khripach 《Journal of Applied Spectroscopy》2009,76(5):617-622
IR spectra of steroid phytohormones of the stigmastane series (22R, 23R)-28-homocastasterone and (22R,23R)-28-homosecasterol
and their isomers (22S,23S)-28-homocastasterone and (22S,23S)-28-homosecasterol have been analyzed. The 28-homocastasterone
molecule contains diol groups in ring A and in the side chain whereas that of 28-homosecasterol has one diol group in the
side chain. The lack of two OH groups in ring A of homosecasterol compared to homocastasterone results in the appearance of
stretching vibrational bands of H–C= (νmax = 3025 cm–1) and –C=C (νmax = 1656 cm–1) groups of ring A. Substantial changes are observed in the area of OH stretching vibrations. Homocastasterones pressed in
KBr possess twice as many OH groups as homosecasterols such that absorption band total intensities in IR spectra of both isomers
caused by H-bonds of the diol groups in the side chain amount to 65% whereas the share of the 2α,3α group is only 35% of the
total intensity. Hence the contribution from the side-chain OH groups of the studied brassinosteroids to the integral optical
density of the bands exceeds that from the ring-A OH groups. In dilute CHCl3 solutions of the brassinosteroids, the conformations
of the brassinosteroid side chains are not the same. As a result, intramolecular H-bonds of different energy are created.
The optical density Dmax in band maxima of free OH groups for homocastasterones is three times higher than that for the corresponding band maxima
of homosecasterol. This implies that Dmax for bands of free OH groups of the homocastasterone ring-A diol group is greater, in contrast with the relatively greater
Dmax for bands of homosecasterol side-chain OH groups bound by an intermolecular H-bond. The homocastasterone diol groups also
form intramolecular Hbonds more actively. The lack of the diol group in ring A of the homosecasterols does not affect the
frequencies of the C=O stretching vibrations. This leads to the conclusion that the C=O group forms intermolecular H-bonds
only with the side-chain OH groups of brassinosteroids pressed in KBr. 相似文献