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1.
Desymmetrization of an Octahedral Coordination Complex Inside a Self‐Assembled Exoskeleton 下载免费PDF全文
Dr. Mark D. Johnstone Eike K. Schwarze Jennifer Ahrens Prof. Dr. Dirk Schwarzer Dr. Julian J. Holstein Dr. Birger Dittrich Dr. Frederick M. Pfeffer Prof. Dr. Guido H. Clever 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10791-10795
The synthesis of a centrally functionalized, ribbon‐shaped [6]polynorbornane ligand L that self‐assembles with PdII cations into a {Pd2 L 4} coordination cage is reported. The shape‐persistent {Pd2 L 4} cage contains two axial cationic centers and an array of four equatorial H‐bond donors pointing directly towards the center of the cavity. This precisely defined supramolecular environment is complementary to the geometry of classic octahedral complexes [M(XY)6] with six diatomic ligands. Very strong binding of [Pt(CN)6]2? to the cage was observed, with the structure of the host–guest complex {[Pt(CN)6]@Pd2L4} supported by NMR spectroscopy, MS, and X‐ray data. The self‐assembled shell imprints its geometry on the encapsulated guest, and desymmetrization of the octahedral platinum species by the influence of the D4h‐symmetric second coordination sphere was evidenced by IR spectroscopy. [Fe(CN)6]3? and square‐planar [Pt(CN)4]2? were strongly bound. Smaller octahedral anions such as [SiF6]2?, neutral carbonyl complexes ([M(CO)6]; M=Cr, Mo, W) and the linear [Ag(CN)2]? anion were only weakly bound, showing that both size and charge match are key factors for high‐affinity binding. 相似文献
2.
Dr. Julian J. Holstein Priv.‐Doz. Dr. Birger Dittrich Miriam Simon Dr. Sylvain Prévost Prof. Dr. Michael Gradzielski Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2018,57(41):13652-13656
A series of metal‐mediated cages, having multiple cavities, was synthesized from PdII cations and tris‐ or tetrakis‐monodentate bridging ligands and characterized by NMR spectroscopy, mass spectrometry, and X‐ray methods. The peanut‐shaped [Pd3L14] cage deriving from the tris‐monodentate ligand L1 could be quantitatively converted into its interpenetrated [5Cl@Pd6L18] dimer featuring a linear {[Pd‐Cl‐]5Pd} stack as an unprecedented structural motif upon addition of chloride anions. Small‐angle neutron scattering (SANS) experiments showed that the cigar‐shaped assembly with a length of 3.7 nm aggregates into mono‐layered discs of 14 nm diameter via solvophobic interactions between the hexyl sidechains. The hepta‐cationic [5Cl@Pd6L18] cage was found to interact with polyanionic oligonucleotide double‐strands under dissolution of the aggregates in water, rendering the compound class interesting for applications based on non‐covalent DNA binding. 相似文献
3.
Lynn S. Lisboa James A. Findlay L. James Wright Christian G. Hartinger James D. Crowley 《Angewandte Chemie (International ed. in English)》2020,59(27):11101-11107
A strategy is presented that enables the quantitative assembly of a heterobimetallic [PdPtL4]4+ cage. The presence of two different metal ions (PdII and PtII) with differing labilities enables the cage to be opened and closed selectively at one end upon treatment with suitable stimuli. Combining an inert PtII tetrapyridylaldehyde complex with a suitably substituted pyridylamine and PdII ions led to the assembly of the cage. 1H and DOSY NMR spectroscopy and ESI mass spectrometry data were consistent with the quantitative formation of the cage, and the heterobimetallic structure was confirmed using single‐crystal X‐ray crystallography. The structure of the host–guest adduct with a 2,6‐diaminoanthraquinone guest molecule was determined. Addition of N,N′‐dimethylaminopyridine (DMAP) resulted in the formation of the open‐cage [PtL4]2+ compound and [Pd(DMAP)4]2+ complex. This process could then be reversed, with the reformation of the cage, upon addition of p‐toluenesulfonic acid (TsOH). 相似文献
4.
Solvent‐Dependent Self‐Assembly Behaviour and Speciation Control of Pd6L8 Metallo‐supramolecular Cages 下载免费PDF全文
James J. Henkelis Dr. Julie Fisher Dr. Stuart L. Warriner Prof. Michaele J. Hardie 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(14):4117-4125
The C3‐symmetric chiral propylated host‐type ligands (±)‐tris(isonicotinoyl)‐tris(propyl)‐cyclotricatechylene ( L1 ) and (±)‐tris(4‐pyridyl‐4‐benzoxy)‐tris(propyl)‐cyclotricatechylene ( L2 ) self‐assemble with PdII into [Pd6L8]12+ metallo‐cages that resemble a stella octangula. The self‐assembly of the [Pd6( L1 )8]12+ cage is solvent‐dependent; broad NMR resonances and a disordered crystal structure indicate no chiral self‐sorting of the ligand enantiomers in DMSO solution, but sharp NMR resonances occur in MeCN or MeNO2. The [Pd6( L1 )8]12+ cage is observed to be less favourable in the presence of additional ligand, than is its counterpart, where L=(±)‐tris(isonicotinoyl)cyclotriguaiacylene ( L1 a ). The stoichiometry of reactant mixtures and chemical triggers can be used to control formation of mixtures of homoleptic or heteroleptic [Pd6L8]12+ metallo‐cages where L= L1 and L1 a . 相似文献
5.
The use of stimuli to induce reversible structural transformations in metallosupramolecular systems is of keen interest to chemists seeking to mimic the way that Nature effects conformational changes in biological machinery. While a wide array of stimuli have been deployed towards this end, stoichiometric changes have only been explored in a handful of examples. Furthermore, switching has generally been between only two distinct states. Here we use a simple 2‐(1‐(pyridine‐4‐methyl)‐1H‐1,2,3‐triazol‐4‐yl)pyridine “click” ligand in combination with PdII in various stoichiometries and concentrations to quantitatively access and cycle between three distinct species: a [PdL2]2+ monomer, a [Pd2L2]4+ dimer, and a [Pd9L12]18+ cage. 相似文献
6.
Self‐Assembly of Five 8‐Hydroxyquinolinate‐Based Complexes: Tunable Core,Supramolecular Structure,and Photoluminescence Properties 下载免费PDF全文
Prof. Dr. Guozan Yuan Weilong Shan Xuelong Qiao Li Ma Prof. Dr. Yanping Huo 《化学:亚洲杂志》2014,9(7):1913-1921
Five new ZnII complexes, namely [Zn3(L)6] ( 1 ), [Zn2(Cl)2(L)2(py)2] ( 2 ), [Zn2(Br)2(L)2(py)2] ( 3 ), [Zn(L)2(py)] ( 4 ), and [Zn2(OAc)2(L)2(py)2] ( 5 ), were prepared by the solvothermal reaction of ZnX2 (X?=Cl?, Br?, F?, and OAc?) salts with a 8‐hydroxyquinolinate ligand (HL) that contained a trifluorophenyl group. All of the complexes were characterized by elemental analysis, IR spectroscopy, and powder and single‐crystal X‐ray crystallography. The building blocks exhibited unprecedented structural diversification and their self‐assembly afforded one mononuclear, three binuclear, and one trinuclear ZnII structures in response to different anions and solvent systems. Complexes 1 – 5 featured four types of supramolecular network controlled by non‐covalent interactions, such as π???π‐stacking, C? H???π, hydrogen‐bonding, and halogen‐related interactions. Investigation of their photoluminescence properties exhibited disparate emission wavelengths, lifetimes, and quantum yields in the solid state. 相似文献
7.
Dr. Stefano Amatori Dr. Gianluca Ambrosi Dr. Mirco Fanelli Dr. Mauro Formica Prof. Vieri Fusi Dr. Luca Giorgi Dr. Eleonora Macedi Dr. Mauro Micheloni Prof. Paola Paoli Dr. Roberto Pontellini Dr. Patrizia Rossi Maria Antonietta Varrese 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(14):4274-4284
Ligand L (4‐(7‐nitrobenzo[1,2,5]oxadiazole‐4‐yl)‐1,7‐dimethyl‐1,4,7,10‐tetra‐azacyclododecane) is a versatile fluorescent sensor useful for CuII, ZnII and CdII metal detection, as a building block of fluorescent metallo‐receptor for halide detection, and as an organelle marker inside live cells. Ligand L undergoes a chelation‐enhanced fluorescence (CHEF) effect upon metal coordination in acetonitrile solution. In all three complexes investigated the metal cation is coordinatively unsaturated; thus, it can bind secondary ligands as anionic species. The crystal structure of [Zn L Cl](ClO4) is discussed. CuII and ZnII complexes are quenched upon halide interaction, whereas the [Cd L ]2+ species behaves as an OFF–ON sensor for halide anions in acetonitrile solution. The mechanism of the fluorescence response in the presence of the anion depends on the nature of the metal ion employed and has been studied by spectroscopic methods, such as NMR spectroscopy, UV/Vis and fluorescence techniques and by computational methods. Subcellular localization experiments performed on HeLa cells show that L mainly localizes in spot‐like structures in a polarized portion of the cytosol that is occupied by the Golgi apparatus to give a green fluorescence signal. 相似文献
8.
Reaction of CdII and ZnII thiocyanate with 3‐acetylpyridine leads to the formation of the new CdII and ZnII coordination compounds [Cd(NCS)2(3‐acetylpyridine)4] ( 1A ), [Cd(NCS)2(3‐acetylpyridine)2]n ( 1B ), [Cd(NCS)2(3‐acetylpyridine)]n ( 1C ) and [Zn(NCS)2(3‐acetylpyridine)2] ( 2A ). Compound 1A consists of discrete complexes, in which the metal centers are octahedrally coordinated by four terminal bonded N‐donor co‐ligands and two terminal N‐bonded thiocyanato anions. In compound 2A the metal centers are only tetrahedrally coordinated by two terminal bonded N‐donor co‐ligands and two terminal N‐bonded thiocyanato anions. In compound 1B the CdII cations are octahedrally coordinated by two terminal bonded N‐donor co‐ligands and four thiocyanato anions. The metal centers are linked by μ‐1, 3 bridging thiocyanato anions into chains. In compound 1C the metal cations are octahedrally coordinated by two μ‐1, 5 bridging 3‐acetyl‐pyridine ligands and four μ‐1, 3 bridging thiocyanato anions building up a three‐dimensional coordination network. Investigations on the thermal degradation behavior of all compounds using simultaneous differential thermoanalysis and thermogravimetry as well as X‐ray powder diffraction and IR spectroscopy prove that on heating compound 2A decompose without the formation of 3‐acetylpyridine‐deficient intermediates. In contrast, for compound 1A a stepwise decomposition is observed, leading to the formation of the 3‐acetylpyridine‐deficient compound [Cd(NCS)2(3‐acetylpyridine)2]n ( 1B ) which decomposes on further heating 相似文献
9.
Lynn S. Lisboa Dr. James A. Findlay Prof. L. James Wright Prof. Christian G. Hartinger Prof. James D. Crowley 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(27):11194-11200
A strategy is presented that enables the quantitative assembly of a heterobimetallic [PdPtL4]4+ cage. The presence of two different metal ions (PdII and PtII) with differing labilities enables the cage to be opened and closed selectively at one end upon treatment with suitable stimuli. Combining an inert PtII tetrapyridylaldehyde complex with a suitably substituted pyridylamine and PdII ions led to the assembly of the cage. 1H and DOSY NMR spectroscopy and ESI mass spectrometry data were consistent with the quantitative formation of the cage, and the heterobimetallic structure was confirmed using single-crystal X-ray crystallography. The structure of the host–guest adduct with a 2,6-diaminoanthraquinone guest molecule was determined. Addition of N,N′-dimethylaminopyridine (DMAP) resulted in the formation of the open-cage [PtL4]2+ compound and [Pd(DMAP)4]2+ complex. This process could then be reversed, with the reformation of the cage, upon addition of p-toluenesulfonic acid (TsOH). 相似文献
10.
Yoko Sakata Shuichi Hiraoka Dr. Mitsuhiko Shionoya Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(11):3318-3325
A series of heteroleptic [Ti 1 2X]? complexes have been selectively constructed from a mixture of TiIV ions, a pyridyl catechol ligand (H2 1 ; H2 1 =4‐(3‐pyridyl)catechol), and various bidentate ligands (HX) in the presence of a weak base, in addition to a previously reported [Ti 1 2(acac)]? (acac=acetylacetonate) complex. Comparative studies of these TiIV complexes revealed that [Ti 1 2(trop)]? (trop=tropolonate) is much more stable than the [Ti 1 2(acac)]? complex, which allows the replacement of acac with trop on the [Ti 1 2(acac)]? complex. This TiIV‐centered site‐selective ligand exchange reaction also takes place on a heteronuclear PdII? TiIV ring complex with the preservation of the PdII‐centered coordination structures. Intra‐ and intermolecular linking between two TiIV centers with a flexible or a rigid bis‐tropolone bridging ligand provided a tetranuclear and an octanuclear PdII? TiIV complex, respectively. These higher‐order structures could be efficiently constructed only through a stepwise synthetic route. 相似文献
11.
The reactions of py‐hz ligands ( L1–L5 ) with Pb(CF3SO3)2?H2O resulted in some rare examples of discrete single‐stranded helical PbII complexes. L1 and L2 formed non‐helical mononuclear complexes [Pb L1 (CF3SO3)2]?CHCl3 and Pb L2 (CF3SO3)2][Pb L2 CF3SO3]CF3SO3?CH3CN, which reflected the high coordination number and effective saturation of PbII by the ligands. The reaction of L3 with PbII resulted in a dinuclear meso‐helicate [Pb2 L3 (CF3SO3)2Br]CF3SO3?CH3CN with a stereochemically‐active lone pair on PbII. L4 directed single‐stranded helicates with PbII, including [Pb2 L4 (CF3SO3)3]CF3SO3?CH3CN and [Pb2 L4 CF3SO3(CH3OH)2](CF3SO3)3?2 CH3OH?2 H2O. The acryloyl‐modified py‐hz ligand L5 formed helical and non‐helical complexes with PbII, including a trinuclear PbII complex [Pb3 L5 (CF3SO3)5]CF3SO3?3CH3CN?Et2O. The high denticity of the long‐stranded py‐hz ligands L4 and L5 was essential to the formation of single‐stranded helicates with PbII. 相似文献
12.
Michael Kampf Rainer Richter Lothar Hennig Andreas Eidner Jens Baldamus Reinhard Kirmse 《无机化学与普通化学杂志》2004,630(15):2677-2686
Synthesis, Structures, NMR and EPR Investigations on Transition Metal Complexes of monofluorosubstituted Acylselenourea Ligands The syntheses and the structures of the ligand N, N‐diethyl‐N′‐(2‐fluoro)benzoylselenourea HEt2mfbsu and the complexes [Ni(Et2mfbsu)2] and [Zn(Et2mfbsu)2] as well as of the ligand N, N‐diisobutyl‐N′‐(2‐fluoro)benzoylselenourea HBui2mfbsu and the complexes [NiII(Bui2mfbsu)2] and [PdII(Bui2mfbsu)2] are reported. The ligands coordinate bidendately forming bischelates. The PdII and NiII complexes are cis coordinated; in [ZnII(Et2mfbsu)2] the ligands are tetrahedrally arranged. The structure of the also obtained bis[diisobutylamino‐(2‐fluorobenzoylimino)methyl]diselenide is reported. The CuII complexes of both selenourea ligands could not be isolated. They were obtained as oils. Their EPR spectra, however, confirm the presence of CuII bischelates unambiguously. Detailed NMR investigations ‐ 1H‐, 13C‐ and 19F‐COSY, HMBC and HMQC ‐ on [MII(Et2mfbsu)2] (M = NiII, ZnII) allow an exact assignment of all signals to the magnetically active nuclei of the complexes. 相似文献
13.
Peter Vranec Ivan Poto
k Peter Repovský 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(12):m370-m376
Bis(5‐chloro‐8‐hydroxyquinolinium) tetrachloridopalladate(II), (C9H7ClNO)2[PdCl4], (I), catena‐poly[dimethylammonium [[dichloridopalladate(II)]‐μ‐chlorido]], {(C2H8N)[PdCl3]}n, (II), ethylenediammonium bis(5‐chloroquinolin‐8‐olate), C2H10N22+·2C9H5ClNO−, (III), and 5‐chloro‐8‐hydroxyquinolinium chloride, C9H7ClNO+·Cl−, (IV), were synthesized with the aim of preparing biologically active complexes of PdII and NiII with 5‐chloroquinolin‐8‐ol (ClQ). Compounds (I) and (II) contain PdII atoms which are coordinated in a square‐planar manner by four chloride ligands. In the structure of (I), there is an isolated [PdCl4]2− anion, while in the structure of (II) the anion consists of PdII atoms, lying on centres of inversion, bonded to a combination of two terminal and two bridging Cl− ligands, lying on twofold rotation axes, forming an infinite [–μ2‐Cl–PdCl2–]n chain. The negative charges of these anions are balanced by two crystallographically independent protonated HClQ+ cations in (I) and by dimethylammonium cations in (II), with the N atoms lying on twofold rotation axes. The structure of (III) consists of ClQ− anions, with the hydroxy groups deprotonated, and centrosymmetric ethylenediammonium cations. On the other hand, the structure of (IV) consists of a protonated HClQ+ cation with the positive charge balanced by a chloride anion. All four structures are stabilized by systems of hydrogen bonds which occur between the anions and cations. π–π interactions were observed between the HClQ+ cations in the structures of (I) and (IV). 相似文献
14.
Complexes [NiI3(mpta)2]I ( 1 ) and [NiI3(ppta)2]I ( 2 ) have been synthesized by reaction of nickel(II) halide salts with ‐1‐methyl‐1‐azonia‐3,5‐diaza‐7‐phosphatricyclo[3.3.1.13,7]decane iodide (mpta+I?) and 1‐(n‐propyl)‐1‐azonia‐3,5‐diaza‐7‐phosphatricyclo[3.3.1.13,7]decane bromide (ppta+Br?) respectively. The crystal structures of compounds 1 and 2 are described and are similar, with both compounds crystallizing in monoclinic space groups. The geometry about both nickel atoms is that of a trigonal bipyramid with the cationic phosphine ligands found in the axial positions and the iodide ligands arranged in the equatorial plane. 相似文献
15.
Miao Du Xian‐He Bu Xue‐Bing Leng Ya‐Mei Guo Ruo‐Hua Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1314-1315
The crystal structure of the title complex, [Ni(C6H14N2)2]Br2, consists of discrete [Ni(C6H14N2)2]2+ cations and bromide counter‐anions. The NiII ion is at the center of symmetry and is four‐coordinated by four nitrogen donors of the mesocyclic ligand 1,5‐diazacyclooctane (DACO) [Ni—N 1.935 (2)–1.937 (2) Å]. The coordination geometry of NiII can be considered as square planar and both DACO ligands take the boat–chair conformation. The bromide anions are hydrogen bonded with the nitrogen donors of the ligands to form a macrocycle‐like ring system. 相似文献
16.
Dr. Witold M. Bloch Dr. Julian J. Holstein Prof. Dr. Wolf Hiller Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2017,56(28):8285-8289
Control over the integrative self-sorting of metallo-supramolecular assemblies opens up possibilities for introducing increased complexity and function into a single self-assembled architecture. Herein, the relationship between the geometry of three ligand components and morphology of three self-sorted heteroleptic [Pd2 L 2 L ′2]4+ cages is examined. Pd-mediated assembly of two bis-monodentate pyridyl ligands with native bite angles of 75° and 120° affords a cis-[Pd2 L 2 L ′2]4+ cage while the same reaction with two ligands with bite angles of 75° and 60° gives an unprecedented, self-penetrating structural motif; a trans-[Pd2(anti- L )2 L ′2]4+ heteroleptic cage with a “doubly bridged figure eight” topology. Each heteroleptic assembly can be formed by cage-to-cage conversion of the homoleptic precursors and morphological control of [Pd2 L 2 L ′2] cages is achieved by selective ligand displacement transformations in a system of three ligands and at least six possible cage products. 相似文献
17.
Yi‐Hang Wen Jian Zhang Jian‐Kai Cheng Zhao‐Ji Li Ye‐Yan Qin Yao Kang Rui‐Feng Hu Yuan‐Gen Yao 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):m248-m249
The crystal structure of the title compound, [Zn(C5H5NS)4](NO3)2, consists of a [Zn(C5H5NS)4]2+ (C5H5NS is pyridinium‐2‐thiolate) cation and two nitrate anions. The central ZnII atom lies at a site with imposed symmetry and is surrounded by four S atoms [Zn—S = 2.3371 (5) Å] from four symmetrical pyridinium‐2‐thiolate ligands in a distorted tetrahedral geometry. There are N—H⋯O hydrogen‐bonding interactions between the pyridinium‐2‐thiolate ligands and nitrate O atoms. In addition, π–π interactions via aromatic N‐containing ligands are discussed. 相似文献
18.
Kai‐Long Zhong Li Chen Lin Chen 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):m62-m64
The title compound, [Cu2(SO4)2(C10H8N2)2(C2H6O2)2(H2O)2]n, contains two crystallographically unique CuII centres, each lying on a twofold axis and having a slightly distorted octahedral environment. One CuII centre is coordinated by two bridging 4,4′‐bipyridine (4,4′‐bipy) ligands, two sulfate anions and two aqua ligands. The second is surrounded by two 4,4′‐bipy N atoms and four O atoms, two from bridging sulfate anions and two from ethane‐1,2‐diol ligands. The sulfate anion bridges adjacent CuII centres, leading to the formation of linear ...Cu1–Cu2–Cu1–Cu2... chains. Adjacent chains are further bridged by 4,4′‐bipy ligands, which are also located on the twofold axis, resulting in a two‐dimensional layered polymer. In the crystal structure, extensive O—H...O hydrogen‐bonding interactions between water molecules, ethane‐1,2‐diol molecules and sulfate anions lead to the formation of a three‐dimensional supramolecular network structure. 相似文献
19.
The synthesis of three new ligands and their coordination behavior towards zinc ions with strongly coordinating anions and cobalt ions with weakly coordinating anions are reported. The ligands have two adjacent imidazolyl‐pyridinyl and pyrazolyl‐pyridinyl binding pockets, respectively, which are linked by a phenol unit. We also investigated the dynamic behavior of the ligand having the imidazolyl‐pyridiyl sidearm in solution. The reaction of the ligands and ZnCl2 yielded complexes of the type [ L Zn2Cl3]. When we used CoII salts with weakly coordinating anions, complexes of the general formula [ L 2Co2]2+ were formed. 相似文献
20.
Unexpected Self‐Sorting Self‐Assembly Formation of a [4:4] Sulfate:Ligand Cage from a Preorganized Tripodal Urea Ligand 下载免费PDF全文
Dr. Komala Pandurangan Dr. Jonathan A. Kitchen Dr. Salvador Blasco Dr. Elaine M. Boyle Bella Fitzpatrick Dr. Martin Feeney Prof. Paul E. Kruger Prof. Thorfinnur Gunnlaugsson 《Angewandte Chemie (International ed. in English)》2015,54(15):4566-4570
The design and synthesis of tripodal ligands 1 – 3 based upon the N‐methyl‐1,3,5‐benzenetricarboxamide platform appended with three aryl urea arms is reported. This ligand platform gives rise to highly preorganized structures and is ideally suited for binding SO42? and H2PO4? ions through multiple hydrogen‐bonding interactions. The solid‐state crystal structures of 1 – 3 with SO42? show the encapsulation of a single anion within a cage structure, whereas the crystal structure of 1 with H2PO4? showed that two anions are encapsulated. We further demonstrate that ligand 4 , based on the same platform but consisting of two bis‐urea moieties and a single ammonium moiety, also recognizes SO42? to form a self‐assembled capsule with [4:4] SO42?: 4 stoichiometry in which the anions are clustered within a cavity formed by the four ligands. This is the first example of a self‐sorting self‐assembled capsule where four tetrahedrally arranged SO42? ions are embedded within a hydrophobic cavity. 相似文献