共查询到20条相似文献,搜索用时 15 毫秒
1.
M. A. Eremina R. M. Nikonova V. I. Lad’yanov V. V. Aksenova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(11):1924-1934
The structural and phase state of the C60-C70 system at various C60/C70 ratios in mixtures obtained by the vaporization of solutions in toluene at ∼98°C was studied by X-ray structure analysis,
differential scanning calorimetry, and infrared spectroscopy. Solid solutions based on the face-centered cubic packing of
C60 are not formed in the C60-C70 system at C70 contents from 0.5 to 50 wt %. The hexagonal close packing of a solid solution of C60 in C70 can be formed as a result of the thermally activated decomposition of the ternary crystal solvate in the C60-C70-C6H5CH3 system. The structural state of multiphase mixtures formed under conditions far from equilibrium is characterized by a high
degree of structure imperfection and greater ability to undergo oxidation compared with C60 and C70. 相似文献
2.
K. N. Semenov D. G. Letenko V. A. Nikitin N. A. Charykov B. M. Aksel’rod 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(1):62-67
Isothermal saturation in ampoules was used to study the solubility of bromine derivatives of fullerene C60Br
n
(n = 6, 8, 24) in α-C10H7Cl and α-C10H7Br in the temperature range of 10–60°C. The corresponding solubility polytherms were characterized, and the compositions of
the equilibrium crystal solvates and the density of the saturated solutions of C60Br
n
were determined. 相似文献
3.
K. Michal Pietrusiewicz Igor I Patsanovsky Vladimir E. Kataev Eleonora A. Ishmaeva Aleksei V. Kataev W. Wieczorek 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The molecular structure, polarity and conformations in solution of 1,3,5-tris(diphenylphosphinoxidemethy1ene)benzene 1,3,5-[Ph2P(0)CH2]3C6H3 have been studied by X-ray, dipole moments and quantum chemistry methods. It have been shown, that in crystal molecule has the conformation in which two diphenylphosphinoxide fragments dispose on one and the same side, but the third - on the other side of central benzene ring plane with torsion angles CSP2-CSP2-CSP3-P 60–80° and CSP2-CSP3-P=O about 50–70°. In solution conformational picture is more rich: side by side with the structures realized in crystal, conformations with all three diphenylphosphinoxide fragments disposed on one and the same side of central benzene ring plane with torsion angles CSP2-CSP2-CSP3-P 70-90° and CSP2-CSP3-P=O about 70–75° become preferable. 相似文献
4.
O. V. Arapov K. N. Semenov N. A. Charykov V. I. Seregin K. V. Nekrasov V. I. Gerasimov 《Russian Journal of Applied Chemistry》2006,79(2):201-204
The liquid (I)-liquid (II) extraction equilibria in the five-component system fullerene C60-fullerene C70-1,2,4-C6H3Cl3-C2H5OH-H2O were studied at 25°C. Isothermal diagrams of distribution of the fullerene components among stratifying liquid phases at a constant content of H2O were obtained. 相似文献
5.
The chloroform solvates of C60 and C70 fullerenes and of the C60/C70 mixture were synthesized and investigated by X-ray powder diffraction. 相似文献
6.
V. V. Aksenova R. M. Nikonova V. L. Lad’yanov V. V. Mukhgalin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(10):1726-1731
The crystal solvates in C60-CCl4 and C70-CCl4 systems obtained by crystallization from CCl4 solution at room temperature were studied by IR Fourier spectroscopy and X-ray diffraction. The C70 · (CCl4) n crystal solvate was obtained and studied for the first time; its hexagonal crystal lattice has unit cell parameters a = 10.658 ± 0.001 Å and c = 10.811 ± 0.002 Å. The temperature ranges of its destruction were determined. 相似文献
7.
Xinye Liu Bo Li Wei Yang Yang-Rong Yao Le Yang Jiaxin Zhuang Xiaomeng Li Peng Jin Ning Chen 《Chemical science》2021,12(7):2488
Chemical functionalization of endohedral metallofullerenes (EMFs) is essential for the application of these novel carbon materials. Actinide EMFs, a new EMF family member, have presented unique molecular and electronic structures but their chemical properties remain unexplored. Here, for the first time, we report the chemical functionalization of actinide EMFs, in which the photochemical reaction of Th@C3v(8)-C82 and U@C2v(9)-C82 with 2-adamantane-2,3′-[3H]-diazirine (AdN2, 1) was systematically investigated. The combined HPLC and MALDI-TOF analyses show that carbene addition by photochemical reaction afforded three isomers of Th@C3v(8)-C82Ad and four isomers of U@C2v(9)-C82Ad (Ad = adamantylidene), presenting notably higher reactivity than their lanthanide analogs. Among these novel EMF derivatives, Th@C3v(8)-C82Ad(I, II, III) and U@C2v(9)-C82Ad(I, II, III) were successfully isolated and were characterized by UV-vis-NIR spectroscopy. In particular, the molecular structures of first actinide fullerene derivatives, Th@C3v(8)-C82Ad(I) and U@C2v(9)-C82Ad(I), were unambiguously determined by single crystal X-ray crystallography, both of which show a [6,6]-open cage structure. In addition, isomerization of Th@C3v(8)-C82Ad(II), Th@C3v(8)-C82Ad(III), U@C2v(9)-C82Ad(II) and U@C2v(9)-C82Ad(III) was observed at room temperature. Computational studies suggest that the attached carbon atoms on the cages of both Th@C3v(8)-C82Ad(I) and U@C2v(9)-C82Ad(I) have the largest negative charges, thus facilitating the electrophilic attack. Furthermore, it reveals that, compared to their lanthanide analogs, Th@C3v(8)-C82 and U@C2v(9)-C82 have much closer metal–cage distance, increased metal-to-cage charge transfer, and strong metal–cage interactions stemming from the significant contribution of extended Th-5f and U-5f orbitals to the occupied molecular orbitals, all of which give rise to their unusual high reactivity. This study provides first insights into the exceptional chemical properties of actinide endohedral fullerenes, which pave ways for the future functionalization and application of these novel EMF compounds.Photochemical reaction of Th@C3v(8)-C82 and U@C2v(9)-C82 with 2-adamantane-2,3′-[3H]-diazirine (AdN2, 1) afforded three isomers of Th@C3v(8)-C82Ad and four isomers of U@C2v(9)-C82Ad (Ad = adamantylidene), respectively. 相似文献
8.
A. M. Kolker A. V. Kozlov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(5):715-719
The solubility of fullerene C60 in tetraline-carbon tetrachloride and tetraline-1,2-dichlorobenzene systems in all compositions of the mixed solvent are
measured in the temperature range of 298.15–338.15 K. It is found that in a mixture of tetraline with 1,2-dichlorobenzene,
the solubility of C60 is considerably higher than in its pure components; in this case, solubility has a maximum in the range of lower temperatures
and compositions of the mixture X
trl = 0.3–0.5. It is established that C60 forms crystal solvates with components of the mixed solvents. Enthalpies and temperatures of incongruent melting of the crystal
solvates are determined by differential scanning calorimetry. 相似文献
9.
Ron S. Dickson Rhonda J. Nesbit Helen Pateras Jennifer M. Patrick Allan H. White 《Journal of organometallic chemistry》1984,265(2):c25-c28
Complexes of formula (η-C5H52Rh2{CF3C2CF3 · RNCO} have been prepared by three methods, from reactions between organic isocyanates and (η-C5H5)2Rh2(CO)(CF3C2CF3) or (η-C5H5)2Rh2(CO)2(CF3C2CF3); by treatment of (η-C5H5)2Rh2(CO)(CF3C2CF3) with organic azides; and by oxidation with Me3NO of the organic isocyanide in (η-C5H5)2Rh2(CO)(CNR)(CF3C2CF3). The crystal and molecular structure of the complex (η-C5H5)2Rh2{CF3C2CF3 · RNCO} with R = Ph has been determined from single crystal X-ray diffraction data. This reveals that the isocyanate has condensed with the hexafluorobut-2-yne to form an amide ligand of the form C(CF3)C(CF3)C(=O)N(R); this bridges the two rhodium atoms in a μ2η3-manner. 相似文献
10.
Natalia V. Avramenko M. V. Korobov Aksana M. Parfenova P. A. Dorozhko Natalia A. Kiseleva P. V. Dolgov 《Journal of Thermal Analysis and Calorimetry》2006,84(1):259-262
In an effort to improve
understanding of dissolution behaviour of fullerenes and their simple chemical
derivatives the binary systems of C60, C70
and the piperazine monoadduct of [60] fullerene C60
N2C4H8
with a series of aromatic solvents have been studied by means of DSC. In certain
systems solid solvates have been found to be the thermodynamically stable
phases relative to saturated solution at room temperature. Identified solid
solvates were characterized by their compositions, temperatures and enthalpies
of incongruent melting transitions. The regularities in thermodynamic stability
of the solvated crystals have been discussed along with dissolution properties
of fullerenes and the derivative. Certain correlations have been observed. 相似文献
11.
U. S. Makhmudov K. K. Turgunov B. Tashkhodjaev A. A. Ibragimov V. A. Saprykina Kh. M. Shakhidoyatov 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(3-4):315-318
By the single-crystal X-ray diffraction the structures of a new polymorphic form and crystal solvates of N-(3-methylthio-1,2,4-thiadiazol-5-yl-aminocarbonylmethyl)cytisine (C16H19N5O2S2) with dioxane and pyridine have been determined. The crystal structures of solvates are isostructural to previously investigated benzene solvated crystal. Crystal solvates are formed at 2:1 ratio of “host” and solvents. Conformations of the host molecules found in the asymmetric unit of crystal solvates are different like it was observed in benzene solvated crystal. A new polymorphic form is obtained from ethyl acetate. 相似文献
12.
Natalia A. Romanova Nadezhda B. Tamm Vitaliy Yu. Markov Alexey A. Goryunkov Lev N. Sidorov Sergey I. Troyanov 《Mendeleev Communications》2012,22(6):297-298
Cs-C60(CF3)6 was synthesized by the reaction of S6-C60(CF3)12 with C60 at 530 °C. Its molecular structure with skew-pentagonal- pyramidal addition pattern was elucidated by single crystal X-ray diffraction. Theoretical DFT calculations were performed to account for a high degree of fragmentation in negative-ion mass spectra. 相似文献
13.
Arapov O. V. Pronkin A. A. Charykov N. A. Seregin V. I. Strel'nikov K. B. 《Russian Journal of Applied Chemistry》2003,76(1):37-43
A new method was proposed for separation of light fullerenes C60 and C70 based on realization of two-phase extraction equilibria in multicomponent fullerene-containing systems C60-C70-solvent I-solvent II and C60-C70-solvent I-solvent II-inert component. The principal possibility and high efficiency of the extraction separation of light fullerenes were demonstrated. 相似文献
14.
Prof. Dr. Steven Stevenson Amanda J. Rothgeb Katelyn R. Tepper Prof. Dr. James Duchamp Prof. Dr. Harry C. Dorn Xian B. Powers Mrittika Roy Prof. Dr. Marilyn M. Olmstead Prof. Dr. Alan L. Balch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(54):12545-12551
Purified samples of Ho3N@C2(22010)-C78 and Tb3N@C2(22010)-C78 have been isolated by two distinct processes from the rich array of fullerenes and endohedral fullerenes present in carbon soot from graphite rods doped with Ho2O3 or Tb4O7. Crystallographic analysis of the endohedral fullerenes as cocrystals with Ni(OEP) (in which OEP is the dianion of octaethylporphyrin) shows that both molecules contain the chiral C2(22010)-C78 cage. This cage does not obey the isolated pentagon rule (IPR) but has two sites where two pentagons share a common C−C bond. These pentalene units bind two of the metal ions, whereas the third metal resides near a hexagon of the cage. Inside the cages, the Ho3N or Tb3N unit is planar. Ho3N@C2(22010)-C78 and Tb3N@C2(22010)-C78 use the same cage previously found for Gd3N@C2(22010)-C78 rather than the IPR-obeying cage found in Sc3N@D3h-C78. 相似文献
15.
Kowalska E. Byszewski P. Diduszko R. Huczko A. Mieczkowski J. 《Journal of Thermal Analysis and Calorimetry》1998,54(1):197-202
The crystalline solvates containing fullerenes and (di)methylnaphthalenes were investigated by thermal analyses and X-ray
diffraction methods. It was found that C60 with (di)methylnaphthalenes forms two types of stable solvates: either at the molar ratio 1:2 decomposing at temperatures
close to 100°C or at 1:1 molar ratio decomposing in the temperature range 120–214°C. Crystalline lattice and thermal stability
of the solvates depends on the structure of the solvent molecules. The strong solute-solvent interaction is also manifested
by the modification of the C60 absorption spectra in solution. The results are discussed using semiempirical quantum chemistry methods.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
N. V. Avramenko A. L. Mirakyan M. V. Korobov E. B. Stukalin 《Journal of Thermal Analysis and Calorimetry》1998,52(3):831-836
Differential scanning calorimetry (DSC) was used to study the binary systems of C60-o-xylene and C70-o-xylene and the ternary system C60-C70-o-xylene. Fullerene C60 formed solvated crystals C60·2C8H10 with incongruent melting point 320 K and with enthalpy of decomposition 31±3 kJ (mol of C60)-1. Two solvated crystals of C70 with incongruent melting points 283 and 369 K, and with decomposition enthalpies 18.5±2.2 and 23.0±1.5 kJ (mol of C70)-1, were formed from o-xylene solutions. Three ternary compositions with C60/C70 mole ratios of 3:1, 1:1 and 1:3 were scanned by DSC.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
B. M. Ginzburg Sh. Tuichiev D. Rashidov S. Kh. Tabarov T. E. Sukhanova M. E. Vylegzhanina A. A. Kutin V. L. Ugolkov 《Polymer Science Series A》2011,53(6):488-501
On the basis of the literature data, a retrospective analysis of the thermodynamic characteristics of dissolution of fullerene
C60 in a series of single-ring aromatic solvents is presented. The effect of the molecular structure of a solvent on its dissolving
capacity with respect to fullerene is studied. The parameter of the boiling temperature of the solvent normalized to its molecular
mass is introduced. The correlation of this parameter with the dissolving capacity of the solvent is discussed. Special emphasis
is placed on the effect of halogen-containing solvents on the dissolution of fullerene and indirectly on the development of
the mechanical characteristics of films prepared from common solutions of fullerene and low-density polyethylene. For comparison,
the films prepared from PE melts modified with low concentrations of fullerene are considered. The film structure is studied
via X-ray analysis, optical microscopy, AFM, small-angle scattering of linearly polarized light, and DSC. The films with the
maximum strength are prepared from solutions in halogen-containing solvents at a concentration of fullerene below 1 wt %.
In this case, spherulites are 5–10 times smaller than those in the films cast from solutions in other solvents. In the films
cast from common solutions of PE and fullerene in bromobenzene, crystal solvates C60 · 2C6H5Br are formed. It seems that the formation of the crystal solvates binds the residual solvent and thus affects the mechanical
behavior of the films, thereby eliminating the plasticizing effect of residual bromobenzene. Localization of fullerene in
various regions of the supramolecular structure of the films is discussed, and the morphology of the separating regions of
the crystal solvate fullerene phase is analyzed. 相似文献
18.
Sanjay M. Tailor Urmila H. Patel 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):944-953
The ability of the antibacterial agent sulfameter (SMT) to form solvates is investigated. The X‐ray crystal structures of sulfameter solvates have been determined to be conformational polymorphs. Both 1,4‐dioxane and tetrahydrofuran form solvates with sulfameter in a 1:1 molar ratio. 4‐Amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide (polymorph III), C11H12N4O3S, (1), has two molecules of sulfameter in the asymmetric unit cell. 4‐Amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide 1,4‐dioxane monosolvate, C11H12N4O3S·C4H8O2, (2), and 4‐amino‐N‐(5‐methoxypyrimidin‐2‐yl)benzenesulfonamide tetrahydrofuran monosolvate, C11H12N4O3S·C4H8O, (3), crystallize in the imide form. Hirshfeld surface analyses and fingerprint analyses were performed to study the nature of the interactions and their quantitative contributions towards the crystal packing. Finally, Hirshfeld surfaces, fingerprint plots and structural overlays were employed for a comparison of the two independent molecules in the asymmetric unit of (1), and also for a comparison of (2) and (3) in the monoclinic crystal system. A three‐dimensional hydrogen‐bonding network exists in all three structures, involving one of the sulfone O atoms and the aniline N atom. All three structures are stabilized by strong intermolecular N—H...N interactions. The tetrahydrofuran solvent molecule also takes part in forming significant intermolecular C—H...O interactions in the crystal structure of (3), contributing to the stability of the crystal packing. 相似文献
19.
Natalia B. Shustova Igor V. Kuvychko Sergey F. Lebedkin Lothar Dunsch Konrad Seppelt Olga V. Boltalina 《Journal of fluorine chemistry》2010,131(11):1198-1212
New experimental results on perfluoroalkylation of C60 and C70 with the use of RfI (Rf = CF3, C2F5, n-C3F7, n-C4F9, and n-C6F13), along with a critical overview of the existing synthetic methods, are presented. For the selected new fullerene (Rf)n compounds we report spectroscopic, electrochemical and structural data, including improved crystallographic data for the isomers of C70(C2F5)10 and C60(C2F5)10, and the first X-ray structural data for the dodecasubstituted perfluoethylated C70 fullerene, C70(C2F5)12, which possesses unprecedented addition pattern. 相似文献
20.
A single isomer of a monofunctionalised C70 fullerene is isolated and characterised using variable temperature NMR spectroscopy. Pendant methylene bromide groups allow for further cycloaddition reactions and a C60-C70 asymmetric fullerene dimer is thus prepared. 相似文献