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1.
In this work, we present scaled variants of the DLPNO‐CCSD(T) method, dubbed as (LS)DLPNO‐CCSD(T) and (NS)DLPNO‐CCSD(T), to obtain accurate interaction energies in supramolecular complexes governed by noncovalent interactions. The novel scaled schemes are based on the linear combination of the DLPNO‐CCSD(T) correlation energies calculated with the standard (LoosePNO and NormalPNO) and modified (Loose2PNO and Normal2PNO) DLPNO‐CCSD(T) accuracy levels. The scaled DLPNO‐CCSD(T) variants provide nearly TightPNO accuracy, which is essential for the quantification of weak noncovalent interactions, with a noticeable saving in computational cost. Importantly, the accuracy of the proposed schemes is preserved irrespective of the nature and strength of the supramolecular interaction. The (LS)DLPNO‐CCSD(T) and (NS)DLPNO‐CCSD(T) protocols have been used to study in depth the role of the CH–π versus π–π interactions in the supramolecular complex formed by the electron‐donor truxene‐tetrathiafulvalene (truxTTF) and the electron‐acceptor hemifullerene (C30H12). (NS)DLPNO‐CCSD(T)/CBS calculations clearly reveal the higher stability of staggered (dominated by CH–π interactions) versus bowl‐in‐bowl (dominated by π–π interactions) arrangements in the truxTTF•C30H12 heterodimer. Hemifullerene and similar carbon‐based buckybowls are therefore expected to self‐assemble with donor compounds in a richer way other than the typical concave–convex π–π arrangement found in fullerene‐based aggregates. © 2017 Wiley Periodicals, Inc.  相似文献   

2.
The photophysical properties of a supramolecular fullerene–porphyrin ensemble resulting from the self‐assembly of a pyrrolidinofullerene–imidazole derivative ( F1 ) with a multimetalloporphyrin array constructed around a hexasubstituted fullerene core ( F(ZnP)12 ) have been investigated. The fullerene hexa‐adduct core of the host system does not play any active role in the cascade of photoinduced events of the supramolecular ensemble, indeed no intercomponent photoinduced processes could be observed in host F(ZnP)12 . In contrast, upon axial coordination with the monosubstituted fullerene guest F1 , a quantitative quenching of the fluorescence signal of the metalloporphyrins was observed for the supramolecular complex [F(ZnP)12(F1) n ] both in polar and nonpolar solvents. In toluene, the supramolecular ensemble exhibits a charge transfer emission centered around 930 nm, suggesting the occurrence of intramolecular face‐to‐face interactions of F1 with neighboring metalloporphyrin moieties within the self‐assembled photoactive array. This mechanism is supported by the fact that a one order of magnitude increase in the binding constant was observed for the supramolecular complex [F(ZnP)12(F1) n ] when compared with a reference system lacking the pyrrolidinofullerene unit. In benzonitrile, a long‐lived charge‐separated state (τ=0.3 μs) has been detected for the supramolecular adduct.  相似文献   

3.
Naphthalene diimides, which are planar, chemically robust and redox‐active, are an attractive class of electron‐deficient dyes, which can undergo a single reversible one‐electron reduction to form stable radical anions in the presence of electron donors upon irradiation. This makes them excellent candidates for organic linkers in the construction of photochromic coordination polymers. Such a photochromic one‐dimensional linear coordination polymer has been prepared using N ,N ′‐bis(3‐carboxyphenyl)naphthalene‐1,8:4,5‐tetracarboximide (H2BBNDI). Crystallization of H2BBNDI with magnesium nitrate in an N ,N ′‐dimethylformamide (DMF)/ethanol/H2O mixed‐solvent system under solvothermal conditions afforded the one‐dimensional coordination polymer catena‐poly[[bis(dimethylformamide‐κO )magnesium(II)]‐bis[μ‐N‐(3‐carboxylatophenyl)‐N ′‐(3‐carboxylphenyl)naphthalene‐1,8:4,5‐tetracarboximide‐κ2O :O ′]], [Mg(C28H13N2O8)2(C3H7NO)2]n . The asymmetric unit contains half of a magnesium cation, one HBBNDI ligand and one DMF molecule. Two partially deprotonated HBBNDI ligands bridge two magnesium cations to form a one‐dimensional chain. Strong inter‐chain π–π interactions between the naphthalene rings of the HBBNDI ligand and the imide rings of adjacent chains provide a two‐dimensional structure. The supramolecular three‐dimensional framework is stabilized by π–π interactions between naphthalene rings of neighbouring two‐dimensional supramolecular networks. The complex exhibits a reversible photochromic behaviour, which may originate from the photoinduced electron‐transfer generation of radicals in the HBBNDI ligand.  相似文献   

4.
The reaction of propane‐1,3‐diamine hydrochloride, 18‐crown‐6 and zinc(II) chloride in methanol solution yields the title complex salt [systematic name: propane‐1,3‐diaminium tetrachloridozincate(II)–1,4,7,10,13,16‐hexaoxacyclooctadecane (1/1)], (C3H12N2)[ZnCl4]·C12H24O6, with an unusual supramolecular structure. The diprotonated propane‐1,3‐diaminium cation forms an unexpected 1:1 supramolecular rotator–stator complex with the crown ether, viz. [C3H12N2(18‐crown‐6)]2+, in which one of the –NH3+ substituents nests in the crown and interacts through N—H...O hydrogen bonding. The other –NH3+ group interacts with the [ZnCl4]2− anion via N—H...Cl hydrogen bonding, forming cation–crown–anion ribbons parallel to [010].  相似文献   

5.
The self‐assembly of the title dinuclear complex, namely (μ‐p‐phenylenediamine‐N,N,N′,N′‐tetraacetato)bis[aqua(1,10‐phenanthroline)nickel(II)] dodecahydrate, [Ni2(C14H12N2O8)(C12H8N2)2(H2O)2]·12H2O, through intricate noncovalent interactions results in a two‐dimensional sheet‐like structure. The dimer lies about an inversion centre at the centre of the p‐phenylenediamine ring. Uncoordinated water molecules form one‐dimensional chains in which cyclic water tetramers act as two types of building blocks. The water molecules play a significant role in the stabilization of the three‐dimensional supramolecular framework. Intramolecular `aryl–metal chelate ring' π–π interactions are also observed.  相似文献   

6.
A biscalix[5]arene–C60 supramolecular structure was utilized for the development of supramolecular fullerene polymers. Di‐ and tritopic hosts were developed to generate the linear and network supramolecular polymers through the complexation of a dumbbell‐shaped fullerene. The molecular association between the hosts and the fullerene were carefully studied by using 1H NMR, UV/Vis absorption, and fluorescence spectroscopy. The formation of the supramolecular fullerene polymers and networks was confirmed by diffusion‐ordered 1H NMR spectroscopy (DOSY) and solution viscometry. Upon concentrating the mixtures of di‐ or tritopic hosts and dumbbell‐shaped fullerene in the range of 1.0–10 mmol L?1, the diffusion coefficients of the complexes decreased, and the solution viscosities increased, suggesting that large polymeric assemblies were formed in solution. Scanning electron microscopy (SEM) was used to image the supramolecular fullerene polymers and networks. Atomic force microscopy (AFM) provided insight into the morphology of the supramolecular polymers. A mixture of the homoditopic host and the fullerene resulted in fibers with a height of (1.4±0.1) nm and a width of (5.0±0.8) nm. Interdigitation of the alkyl side chains provided secondary interchain interactions that facilitated supramolecular organization. The homotritopic host generated the supramolecular networks with the dumbbell‐shaped fullerene. Honeycomb sheet‐like structures with many voids were found. The growth of the supramolecular polymers is evidently governed by the shape, dimension, and directionality of the monomers.  相似文献   

7.
A set of neutral and anionic carborane derivatives in which the styrenyl fragment is introduced as a fluorophore group has been successfully synthesized and characterized. The reaction of the monolithium salts of 1‐Ph‐1,2‐C2B10H11, 1‐Me‐1,2‐C2B10H11 and 1,2‐C2B10H12 with one equivalent of 4‐vinylbenzyl chloride leads to the formation of compounds 1 – 3 , whereas the reaction of the dilithium salt of 1,2‐C2B10H12 with two equivalents of 4‐vinylbenzyl chloride gives disubstituted compound 4 . The closo clusters were degraded using the classical method, KOH in EtOH, to afford the corresponding nido species, which were isolated as tetramethylammonium salts. The crystal structure of the four closo compounds 1 – 4 were analyzed by X‐ray diffraction. All compounds, except 1 , display emission properties, with quantum yields dependent on the nature of the cluster (closo or nido) and the substituent on the second Ccluster atom. In general, closo compounds 2 – 4 exhibit high fluorescence emission, whereas the presence of a nido cluster produces a decrease of the emission intensity. The presence of a phenyl group bonded to the Ccluster results in an excellent electron‐acceptor unit that produces a quenching of the fluorescence. DFT calculations have confirmed the charge‐separation state in 1 to explain the quenching of the fluorescence and the key role of the carboranyl fragment in this luminescent process.  相似文献   

8.
Representatives of two classes of hexakis‐adducts of C60 were prepared by templated synthesis strategies. Compound 8 with a dipyridylmethano addend in a pseudo‐octahedral addition pattern was obtained by DMA‐templated addition (DMA=9,10‐dimethylanthracene; Scheme 1) and served as the starting material for the first supramolecular fullerene dimer 2 . Hexakis‐adduct 12 also possesses a pseudo‐octahedral addition pattern and was obtained by a sequence of tether‐directed remote functionalization, tether removal, and regioselective bis‐functionalization (Scheme 2). With its two diethynylmethano addends in trans‐1 position, it is a precursor for fascinating new oligomers and polymers that feature C60 moieties as part of the polymeric backbone (Fig. 1). With the residual fullerene π‐electron chromophore reduced to a `cubic cyclophane'‐type sub‐structure (Fig. 4), and for steric reasons, 8 and 12 no longer display electrophilic reactivity. As a representative of the second class of hexakis‐adducts, (±)‐ 1 , which features six addends in a distinct helical array along an equatorial belt, was prepared by a route that involved two sequential tether‐directed remote functionalization steps (Schemes 3 and 5). In compound (±)‐ 1 , π‐electron conjugation between the two unsubstituted poles of the carbon sphere is maintained via two (E)‐stilbene‐like bridges (Fig. 4). As a result, (±)‐ 1 features very different chemical reactivity and physical properties when compared to hexakis‐adducts with a pseudo‐octahedral addition pattern. Its reduction under cyclic voltammetric conditions is greatly facilitated (by 570 mV), and it readily undergoes additional, electronically favored Bingel additions at the two sterically well‐accessible central polar 6‐6 bonds under formation of heptakis‐ and octakis‐adducts, (±)‐ 30 and (±)‐ 31 , respectively (Scheme 6). The different extent of the residual π‐electron delocalization in the fullerene sphere is also reflected in the optical properties of the two types of hexakis‐adducts. Whereas 8 and 12 are bright‐yellow (end‐absorption around 450 nm), compound (±)‐ 1 is shiny‐red, with an end‐absorption around 600 nm. This study once more demonstrates the power of templated functionalization strategies in fullerene chemistry, providing addition patterns that are not accessible by stepwise synthetic approaches.  相似文献   

9.
曾和平 《中国化学》2002,20(10):1007-1011
Photoinduced electron transfer(PET) processes between C60-C6H8SO and Tetrathiafulvalene(TTF) have been studied by nanosecond laser photolysis.Quantrm yiekds(φet) and rate constants of electron transfer(ket) from TTF to excited triplet state of[60] fullerene-containing cyclic sulphoxide in benzonitrile(BN) have been evaluated by observing the transient absorption bands in the NIR region.With the decay of excited triplet state of [60]fullerene-containing cyclic suplhoxide,the rise of radical anion of [60]fullerene-containing cyclic sulphoxinde is observed.  相似文献   

10.
The title free base porphyrin compound forms hydrogen‐bonded adducts with N,N‐dimethylformamide, C44H30N4O4·4C3H7NO, (I), a mixture of N,N‐dimethylformamide and water, C44H30N4O4·4C3H7NO·H2O, (II), and a mixture of N,N‐dimethylacetamide and water, C44H30N4O4·6C3H7NO·2H2O, (III). Total solvation of the four hydroxy functions of the porphyrin molecules characterizes all three compounds, thus preventing its supramolecular association into extended network architectures. In (I), the asymmetric unit consist of two five‐component adduct species, while in (III), the nine‐component entities reside on centres of inversion. This report provides the first structural characterizations of the free base tetra(hydroxyphenyl)porphyrin. It also demonstrates that the presence of strong Lewis bases, such as dimethylformamide or dimethylacetamide, in the crystallization mixture prevents direct supramolecular networking of the porphyrin ligands via O—H...O—H hydrogen bonds, due to their competing O—H...N(base) interaction with the hydroxy functions. The crystal packing of compounds (I)–(III) resembles that of other hydrogen‐bonding‐assisted tetraarylporphyrin clathrates.  相似文献   

11.
Copper(II) coordination polymers have attracted considerable interest due to their catalytic, adsorption, luminescence and magnetic properties. The reactions of copper(II) with 2‐amino‐4‐sulfobenzoic acid (H2asba) in the presence/absence of the auxiliary chelating ligand 1,10‐phenanthroline (phen) under ambient conditions yielded two supramolecular coordination polymers, namely (3‐amino‐4‐carboxybenzene‐1‐sulfonato‐κO1)bis(1,10‐phenanthroline‐κ2N,N′)copper(II) 3‐amino‐4‐carboxybenzene‐1‐sulfonate monohydrate, [Cu(C7H6N2O5S)(C12H8N2)2](C7H6N2O5S)·H2O, (1), and catena‐poly[[diaquacopper(II)]‐μ‐3‐amino‐4‐carboxylatobenzene‐1‐sulfonato‐κ2O4:O4′], [Cu(C7H6N2O5S)(H2O)2]n, (2). The products were characterized by FT–IR spectroscopy, thermogravimetric analysis (TGA), solid‐state UV–Vis spectroscopy and single‐crystal X‐ray diffraction analysis, as well as by variable‐temperature powder X‐ray diffraction analysis (VT‐PXRD). Intermolecular π–π stacking interactions in (1) link the mononuclear copper(II) cation units into a supramolecular polymeric chain, which is further extended into a supramolecular double chain through interchain hydrogen bonds. Supramolecular double chains are then extended into a two‐dimensional supramolecular double layer through hydrogen bonds between the lattice Hasba anions, H2O molecules and double chains. Left‐ and right‐handed 21 helices formed by the Hasba anions are arranged alternately within the two‐dimensional supramolecular double layers. Complex (2) exhibits a polymeric chain which is further extended into a three‐dimensional supramolecular network through interchain hydrogen bonds. Complex (1) shows a reversible dehydration–rehydration behaviour, while complex (2) shows an irreversible dehydration–rehydration behaviour.  相似文献   

12.
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, cdaH3) reacts with MnCl2·2H2O in the presence of 2‐amino‐4‐methylpyrimidine in water to afford the tetranuclear title complex, [Mn4(C8H3NO5)4(H2O)10]·3.34H2O, built through carboxylate bridging. The tetranuclear complex sits on a centre of inversion at (, , ). In the crystal, discrete undecameric (H2O)10.34 water clusters (involving both coordinated and uncoordinated water molecules, with one site of an uncoordinated water molecule not fully occupied) assemble these tetranuclear MnII complex units via an intricate array of hydrogen bonding into an overall three‐dimensional network. The degree of structuring of the (H2O)10.34 supramolecular association of water molecules observed in the present compound, imposed by its environment and vice versa, will be discussed in comparison to that observed for the (H2O)14 supramolecular clusters in the case of the dinuclear complex [Mn2(cdaH)2(H2O)4]·4H2O [Ghosh et al. (2005). Inorg. Chem. 44 , 3856–3862].  相似文献   

13.
The title ionic compound, [Ni(C12H12N2)(H2O)4]SO4·H2O, is composed of an NiII cation coordinated by a chelating 4,4′‐dimethyl‐2,2′‐bipyridine ligand via its two N atoms [mean Ni—N = 2.056 (2) Å] and by four aqua ligands [mean Ni—O = 2.073 (9) Å], the net charge being balanced by an external sulfate anion. The whole structure is stabilized by a solvent water molecule. Even though the individual constituents are rather featureless, they generate an extremely complex supramolecular structure consisting of a central hydrogen‐bonded two‐dimensional hydrophilic nucleus made up of complex cations, sulfate anions and coordinated and solvent water molecules, with pendant hydrophobic 4,4′‐dimethyl‐2,2′‐bipyridine ligands which interact laterally with their neighbours viaπ–π interactions. The structure is compared with closely related analogues in the literature.  相似文献   

14.
The title compound, C9H12N2O3, crystallizes with two mol­ecules in the asymmetric unit. There is extensive hydrogen bonding which results in the formation of a two‐dimensional corrugated sheet. This supramolecular structure is determined by the formation of hydrogen‐bonded chains resulting from the presence of a 6‐amino group and an ethoxy­carbonyl group as substituents on a pyridine ring in relative para positions which constitute a π‐electron `push–pull' system.  相似文献   

15.
The CeIII ion in the title complex, [Ce(NO3)3(C13H12N4O)2], is 12‐coordinated by six chelating nitrate O atoms and six donors (2 O and 4 N atoms) of two N′‐[1‐(2‐pyridyl)ethylidene]isonicotinohydrazide ligands, exhibiting a bicapped pentagonal‐antiprism‐type coordination geometry. The title complex possesses C2 point symmetry and is located on a twofold crystallographic axis. Each molecule is linked with four surrounding molecules by four N—H...N hydrogen bonds, resulting in an extended two‐dimensional layer parallel to the ab plane, while π–π interactions between pyridine rings from neighboring complex molecules connect the two‐dimensional layers into a three‐dimensional cerium–organic supramolecular structure.  相似文献   

16.
The reactivity of the explosive tetryl (N‐methyl‐N,2,4,6‐tetranitroaniline; Mw = 287 u) was studied using electrospray ionization in negative mode. The main species detected in the spectrum corresponds to the ion observed at m/z 318 (previously assumed to be the odd‐electron ion [tetryl + HNO]‐?, C7H6O9N6). In this study, we show using D‐labeling combined with high‐resolution mass spectrometry that this species corresponds to an even‐electron anion (i.e. C8H8O9N5), resulting from the formation of a Meisenheimer complex between tetryl and the methanol used as the solvent. Fragmentation of this complex under CID conditions revealed an unexpected fragment: the formation of a 2,4,6‐trinitrophenoxide anion at m/z 228. 18O‐labeling combined with quantum chemical calculations helped us better understand the reaction pathways and mechanisms involved in the formation of this product ion. This occurs via a transition state leading to a SN2‐type reaction, consequently evolving toward an ion‐dipole complex. The latter finally dissociates into deprotonated picric acid. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

17.
Herein the synthesis, characterization, and organization of a first‐generation dendritic fulleropyrrolidine bearing two pending porphyrins are reported. Both the dendron and the fullerene derivatives were synthesized by CuI‐catalyzed alkyne–azide cycloaddition (CuAAC). The electron‐donor–acceptor conjugate possesses a shape that allows the formation of supramolecular complexes by encapsulation of C60 within the jaws of the two porphyrins of another molecule. The interactions between the two photoactive units (i.e., C60 and Zn–porphyrin) were confirmed by cyclic voltammetry as well as by steady‐state and time‐resolved spectroscopy. For example, a shift of about 85 mV was found for the first reduction of C60 in the electron‐donor–acceptor conjugate compared with the parent molecules, which indicates that C60 is included in the jaws of the porphyrin. The fulleropyrrolidine compound exhibits a rich polymorphism, which was corroborated by AFM and SEM. In particular, it was found to form supramolecular fibrils when deposited on substrates. The morphology of the fibrils suggests that they are formed by several rows of fullerene–porphyrin complexes.  相似文献   

18.
The atom transfer radical addition polymerization (ATRAP) of fullerene to give poly(fullerene)s (PFs) for organic electronics is explored. Quantum chemistry maps the expected electronic behavior of PFs with respect to common electron acceptors, namely fullerene, phenyl‐C61‐butyric acid methyl ester and its bis‐adduct, and mono‐ and bis‐indine‐fullerene derivatives. Surprisingly, it is found that PFs should demonstrate electron affinities and LUMO energy levels closer to the bis‐derivatives than the mono‐adducts, even though only one C60 double‐bond is used in PF chain formation. A self‐consistent library of PFs is synthesized and a correlation between structural characteristics and molecular weights is found. While comonomers with –OC16H33 linear side‐chains lead to the highest known ATRAP molecular weights of 21000 g mol ? 1, like‐for‐like, branched side‐chains permit syntheses of higher molecular weights and more soluble polymers. Of the series, however, PFs with ‐OC12 side‐chains are expected to be of the greatest interest for opto‐electronic applications due to their ease of handling and highest regioregularity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 1345–1355  相似文献   

19.
A technique for improving the sensitivity of high mass molecular analysis is described. Three carbon species, fullerenes, single walled carbon nanotubes, and highly ordered pyrolytic graphite are introduced as matrices for the secondary ion mass spectrometry analysis of cyclodextrin (C42H70O35, 1134 u). The fullerene and nanotubes are deposited as single deposition, and 10, 20, or 30 deposition films and cyclodextrin is deposited on top. The cyclodextrin parent-like ions and two fragments were analyzed. A 30 deposition fullerene film enhanced the intensity of cationized cyclodextrin with Na by a factor of 37. While the C6H11O5 fragment, corresponding to one glucopyranose unit, increased by a factor of 16. Although fragmentation on fullerene is not suppressed, the intensity is twice as low as the parent-like ion. Deprotonated cyclodextrin increases by 100× and its C8H7O fragment by 10×. While the fullerene matrix enhances secondary ion emission, the nanotubes matrix film generates a basically constant yield. Graphite gives rise to lower intensity peaks than either fullerene or nanotubes. Scanning electron microscopy and atomic force microscopy provide images of the fullerene and nanotubes deposition films revealing flat and web structured surfaces, respectively. A “colliding ball” model is presented to provide a plausible physical mechanism of parent-like ion enhancement using the fullerene matrix.  相似文献   

20.
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