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1.
采用缓慢挥发溶剂的方法合成了硫原子桥联芳基取代四硫富瓦烯(Ar-S-TTF)与碘的3种电荷转移复合物(1)(I3)·I2、(2)(I5)·I2和(32+)(I32,采用单晶X射线衍射、紫外可见光谱、循环伏安对其进行了表征。复合物(1)(I3)·I2C2/c空间群,1呈椅式构型。化合物1与碘之间在溶液中和复合物中电荷转移一致。复合物(2)(I5)·I2P1空间群,2呈椅式构型。复合物(32+)(I32Pbca空间群,32+呈独特的平面构型。化合物23与碘之间在溶液中和复合物中呈现不同的电荷转移。复合物中聚碘阴离子呈现不同的堆积结构:由I3-或I5-/I2组成的一维链状和I3-/I2组成的二维网格状。  相似文献   

2.
左琦  马龙飞 《无机化学学报》2023,39(10):1869-1876
采用缓慢挥发溶剂的方法合成了硫原子桥联芳基取代四硫富瓦烯(Ar-S-TTF)与碘的3种电荷转移复合物(1)(I3)·I2、(2)(I5)·I2和(32+)(I3)2,采用单晶X射线衍射、紫外可见光谱、循环伏安对其进行了表征。复合物(1)(I3)·I2C2/c空间群,1呈椅式构型。化合物1与碘之间在溶液中和复合物中电荷转移一致。复合物(2)(I5)·I2P1空间群,2呈椅式构型。复合物(32+)(I3)2Pbca空间群,32+呈独特的平面构型。化合物23与碘之间在溶液中和复合物中呈现不同的电荷转移。复合物中聚碘阴离子呈现不同的堆积结构:由I3-或I5-/I2组成的一维链状和I3-/I2组成的二维网格状。  相似文献   

3.
Abstract

1-D coordination polymers, 1[Zn(fl)2]·2EtOH and 1[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated.  相似文献   

4.
5.
The macrocyclic complex [Ni2(L)(OAc)]ClO4 ( 1 ) adsorbs up to 17 molar equivalents (>270 wt %) of iodine, although it does not exhibit permanent porosity. Vibrational spectroscopic and crystallographic studies reveal that two I2 molecules are captured by means of thiophenolate→I2 charge‐transfer interactions, which enable the diffusion and sorption of further I2 molecules in a polyiodide‐like network. The efficient sorption and desorption characteristics make this material suitable for accommodation, sensing, and slow release of I2.  相似文献   

6.
The iodine binding capacity (IBC) of glycogen is around 0.30% (w/w) at 3°C. The amount of iodine complexed comprises about 12.5% of the mass of glycogen that takes part in the glycogen–iodine (GI) complex formation. This suggests involvement of four iodine atoms for every 25 anhydroglucose units (AGU, C6H10O5). Since the chromophore is due to the I4 unit within the helix of 11 AGUs, only 44% of the AGUs (11 out of 25) are involved in the complex formation. The heat of formation of the GI complex is around −40 kJ/mol of I2 bonded. These results suggest remarkable similarities with those of the amylopectin–iodine (API) complex. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1409–1412, 1997  相似文献   

7.
Kinetics of oxidation of semicarbazide (SC) by iodamine-T (IAT), iodine monochloride and aqueous iodine has been studied in aqueous perchloric acid medium. The rate laws followed by the oxidation of SC were determined. The rates decreased slightly with increase in ionic strength of the medium in IAT and ICI oxidations, while the reverse trend was observed with I2. Decrease in dielectric constant of the medium increased the rates with IAT and ICI, while it decreased the rate in I2 oxidations. Addition of the reduced product,p-toluene-sulphonamide had no effect on the rate with IAT. Addition of I had slight negative and positive effects on the rates of oxidations with IAT and ICI, respectively, but the negative effect was considerable in I2 oxidations. Mechanisms consistent with the observed rate laws have been proposed and discussed. Rate determining steps have been identified and their coefficients calculated. These constants were used to predict the rate constants from the deduced rate laws as [SC], [H+] and [I] varied. Reasonable agreement between the calculated constants and experimental values provide support for the suggested mechanisms.  相似文献   

8.
Glycogen–iodine (GI) complex formation has been studied at different concentrations of iodine and glycogen. For each glycogen concentration (0.25, 0.125, 0.0625, 0.0313 g/L), the iodine concentration was varied from 0.0317 to 1.59 g/L and the absorbance readings were taken at 453 and 560 nm (GI wavelengths of maximum absorbance). The 453 nm absorbance curves for the GI solution (GI complex and unreacted iodine), and that of the pure iodine solution (without glycogen) level off at a high iodine concentration, and give a peak in the subtracted curve. The 560 nm curves consistently increase in absorbance, and no peak is noticed in the subtracted curve. The spectra of concentrated iodine solutions in water and alcohol suggest the formation of neutral iodine clusters. We suggest that these iodine clusters do not react with glycogen, and that the GI complex formation takes place by the addition of I2 molecules. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 927–931, 1997  相似文献   

9.
A partial hydrolysis of amylose followed by the addition of iodine provides a spectrum almost identical to that of the amylopectin–iodine (API) complex suggesting the involvement of smaller “amylose-like” units in the API complex. Our theoretical studies on different polyiodine and polyiodide species suggest that a nearly linear I4 unit stabilized within the cavity of a small “amylose-like” helix is responsible for the characteristic API spectrum. Since there are 2.75 anhydroglucose residues (AGU) for every iodine atom in the amylose–iodine (AI) complex and a structural similarity exists between the API and the AI (amylose–iodine) complexes, we identify (C6H10O5)11I4 to be the chromophore in the API complex. © 1994 John Wiley & Sons, Inc.  相似文献   

10.
The interaction of fullerene C60 with molecular iodine in organic solvents was studied. The stoichiometry of the complex formed, C60I2=13, was determined spectrophotometrically and by the interphase distribution technique. The constant of the formation of the adduct in toluene was calculated to be logK=8.9±0.3.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 481–483, March, 1995.  相似文献   

11.

The crystal and molecular structure of the reaction product of imidazolidine-2-thione and molecular iodine of the composition (C3H6N2S)2?3I2 was established by X-ray diffraction. The crystal structure is composed of strongly connected five-component associates consisting of three I2 molecules and two heterocyclic molecules. Quantum chemical calculations followed by the topological analysis of the electron density function provided an estimate of the strongest intermolecular interactions in the crystal structure of the molecular adduct.

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12.
The reaction of [RhCl2(HPhL)(PhL)] with MII(ClO4)2·6H2O in presence of alkali has furnished trinuclear [RhCl2(PhL)2]2M(H2O)2·H2O (HPhL is phenylazobenzaldoxime; M = Mn, Co, Ni). A similar reaction with MI(PPh3)2NO3 yielded binuclear [RhCl2(PhL)2]M(PPh3)2 (M = Cu, Ag). In these molecules the oximato group acts as a bridge between RhIII (bonded at N) and MII or MI (bonded at O). In structurally characterized [RhIIICl2(PhL)2]2Mn(H2O)2.H2O the centrosymmetric distorted octahedral MnO6 coordination sphere is spanned by four oximato oxygen atoms and two water molecules lying in trans position. In the lattice the neighbouring molecules are held together by H2O⋯H2O⋯H2O hydrogen bonds generating infinite zigzag chains. The manganese atoms lie parallel to the C-axis, the shortest Mn...Mn distance being 7.992 ?. Magnetic exchange interactions if any are small as seen in room temperature magnetic moments. The manganese system displays a strong EPR signal near g = 2.00. In the complex [RhCl2(PhL)2]Cu(PPh3)2 the copper atom is coordinated to two oximato oxygen atoms and the two phosphorus atoms in a distorted tetrahedral geometry. The softness of the phosphine ligand is believed to sustain the stable coordination of hard oximato oxygen to soft CuI. The coordination sphere of the RhIII atom in both the complexes is uniformly trans-RhN4Cl2.  相似文献   

13.
The dinuclear complex [Cu2(HL)2(H2O)2](ClO4)2 ( 1 ) [H2L = 5′‐(pyridin‐2‐yl)‐1‐H,2′‐H‐3, 3′‐bis(1, 2,4‐triazole)] was obtained and fully characterized. It exhibits a centrosymmetry configuration, in which each copper(II) ion is pentacoordinate with four nitrogen atoms of two triazole ligands and one oxygen atom from a water molecule. The net atomic charges distribution and atomic orbital contribution to frontier molecular orbitals were obtained using the Gaussian 98 program with Hartree‐Fock method at LANL2DZ level, indicating that the copper(II) ion has the potential to accept the electron of O2 · –. The complex showed quasi‐reversible one‐electron CuII/CuI redox waves with redox potentials of –0.034 V. The SOD‐like activity (IC50) of 1 was measured to be 0.18 ± 0.01 μM by xanthine/xanthine oxidase‐NBT assay at pH 7.8. The relatively high SOD activity suggests that the positive charge of protonated triazole can effectively steer O2 · – to and from the active copper ion.  相似文献   

14.
The First Polyiodo Complex – Triethylsulfoniumtriiodomercurate(II)-tris(diiodine), (Et3S)[Hg2I6]1/2 · 3 I2 After Raman spectroscopic investigation of the system HgI2/Et3SIx, x = 3, 5, 7, triethylsulfoniumtriiodomercuratetris(diiodine), (Et3S)[Hg2I6]1/2 · 3 I2 was synthesized by reacting of HgI2 and liquid Et3SI7. The compound crystallizes at room temperature triclinically in the space group P1 with a = 879.4(7), b = 1 209.1(5), c = 1 291.5(5) pm, α = 96.16(3)°, β = 103.82(6)°, γ = 99.05(5)° and Z = 2. The crystal structure is composed of disordered Et3S+ cations, the centrosymmetric complex anion [HgI2/2I2]22? and three connecting iodine molecules I2.  相似文献   

15.
Gossypol has been obtained in the zeolite-like form by desolvation of the 1:1 unstable solvate with dichloromethane. It demonstrates a high potential for an uptake of molecular iodine from the environment. In a case of single crystals a stable inclusion compound (gossypol)8·I2, preserving the crystal structure of the zeolite-like form, has been prepared. The iodine molecules occupy large cavities of the channels and are inclined as confirmed by the absence of a strong dichroism. The iodine molecules can be removed with the help of vacuum giving back to the zeolite-like form. Supplementary Data relating to this article are deposited with the Cambridge Crystallographic Data Centre as supplementary publication No. CCDC 226180.  相似文献   

16.
《中国化学会会志》2017,64(11):1294-1302
In this work, a nickel(II) synergist complex with methyl isonicotinate (BI, a short chain analog of n‐hexyl 3‐pyridinecarboxylate ester) and naphthalene‐2‐sulfonic acid (HNS, a short chain analog of dinonylnaphthalene sulfonic acid) was synthesized and studied by single‐crystal X‐ray diffraction. The nickel(II) complex crystallizes in the monoclinic P 21/n space group with the composition [Ni(H2O)4(BI)2](NS)2·2H2O. The Ni(II) ions of these crystallographically independent molecules lie on an inversion center, forming a trans‐form distorted octahedral coordination structure. The nickel(II) ions can coordinate with four water molecules and two BI ligands, resulting in a mono‐metallic structure [Ni(H2O)4(BI)2]2+. There is no direct interaction between nickel(II) and sulfonic oxygen atoms of the sulfonate anions, but hydrogen bonds form between sulfonic oxygen atoms and water molecules in the synergist complex. In order to further elucidate the solution structure of the nickel(II) complexes with the actual synergistic mixture containing n‐hexyl 3‐pyridinecarboxylate ester and dinonylnaphthalene sulfonic acid in the nonpolar organic phase, the nickel(II) complexes were studied by electrospray ionization mass spectrometry. The results indicated that the extracted nickel(II) complexes in the nonpolar solvent have a similar coordination structure as that of the crystalline nickel(II) synergist complex.  相似文献   

17.
At T < 250 K, the polyiodide inclusion complex (α-cyclodextrin)2·Sr0.5·I5·17H2O displays two separate relaxation processes due to both the frozen-in proton motions in an otherwise ordered H-bonding network and the order–disorder transition of some normal H-bonds to flip-flop ones. At T>250 K, the AC-conductivity is dominated by the combinational contributions of the disordered water network, the mobile Sr2+ ions, the polyiodide charge-transfer interactions and the dehydration process. The evolution of the Raman spectroscopic data with temperature reveals the coexistence of four discrete pentaiodide forms. In form (I) (I 3·I2 ? I2·I 3), the occupancy ratio (x/y) of the central I ion differs from 50/50. In form (IIa) (I2·I·I2) x/y = 50/50, whereas in its equivalent form (IIb) (I2·I·I2) * as well as in form (III) (I 3·I2), x/y = 100/0 (indicative of full occupancy). Through slow cooling and heating, the inverse transformations (I) → (IIa) and (IIa) → (I) occur, respectively.

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18.
Crystal Structures of the Phosphoraneiminato Complex [INi(NPMe3)]4 · C4H8O · C7H8 and of the Phosphanimine Complex [INi{Me2Si(NPMe3)2}(HNPMe3)]+I The phosphoraneiminato complex [INi(NPMe3)]4 was obtained by reaction of NiI2 in molten Me3SiNPMe3 in the presence of potassium fluoride at 200 °C. Dark‐green single crystals of [INi(NPMe3)]4 · C4H8O · C7H8 were formed from THF‐toluene solution. According to the X‐ray crystal structure determination the complex has a Ni4N4 heterocubane core and its symmetry deviates only marginally from Td (space group Pca21, Z = 4, a = 3160.7(6), b = 1001.5(1), c = 1422.6(8) pm). The [INi(NPMe3)]4 molecules are stacked to columns parallel to b, with a nearly tetragonal pattern in projection on (010). The solvent molecules reside in channels between the columns. A side product of the synthesis were blue single crystals of the phosphanimine complex [INi{Me2Si(NPMe3)2}(HNPMe3)]+I. The crystal structure determination (space group Pca21, Z = 4, a = 1213.3(4), b = 1582.7(6), c = 1339.7(4) pm) revealed a distorted tetrahedral coordination of the Ni atom in the cation; the coordinated atoms are the two N atoms of the chelating bis(phosphane)imine molecule, the N atom of the phosphaneimine molecule HNPMe3 and one iodo ligand.  相似文献   

19.
The reactions of 1-methylimidazoline-2-thione and its chemical oxidation product, viz., 2,2′-dithiobis(1-methylimidazolin-2-yl) diiodide, with molecular iodine were studied by UV-Vis spectroscopy. The crystal and molecular structure of the compound of composition [(C3H2N2)(HCH3)S]2(I3)2I2 was established by X-ray diffraction. In the crystal structure, the dications and the triiodide anions form mixed stacks, between which iodine molecules are located. The dications, anions, and iodine molecules are linked by numerous intermolecular interactions to form three-dimensional supramolecular associates.  相似文献   

20.
The molecular interactions between phosphorous ylide (PY) and HX molecules (X?=?F, CN, and N3) were investigated using the MP2 method at 6-311++G(2d,2p) basis set. Three different patterns including non-classical hydrogen bond H···C, X···P interaction and classical hydrogen bond H···X were found for complex formation between PY and HX molecules. From the predicted models, stability of the H···C type complexes are greater than other types. Quantum theories of atoms in molecules and natural bond orbitals methods have been applied to analyze the intermolecular interactions. Good correlations have been found between the interaction energies (SE), the second-order perturbation energy E (2), and the charge transfer qCT in the studied systems.  相似文献   

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