Layer-by-layer-assembled multilayer films of polyelectrolyte-stabilized surfactant micelles for the incorporation of noncharged organic dyes

Noncharged pyrene molecules were incorporated into multilayer films by first loading pyrene into poly(acrylic acid) (PAA)-stabilized cetyltrimethylammonium bromide (CTAB) micelles (noted as PAA&(Py@CTAB)) and then layer-by-layer (LbL) assembled with poly(diallyldimethylammonium chloride) (PDDA). The stable incorporation of pyrene into multilayer films was confirmed by quartz crystal microbalance (QCM) measurements and UV-vis absorption spectroscopy. The resultant PAA&(Py@CTAB)/PDDA multilayer films show an exponential growth behavior because of the increased surface roughness with increasing number of film deposition cycles. The present study will open a general and cost-effective avenue for the incorporation of noncharged species, such as organic molecules, nanoparticles, and so forth, into LbL-assembled multilayer films by using polyelectrolyte-stabilized surfactant micelles as carriers.     

Preparation of stable and metastable coordination compounds: insight into the structural, thermodynamic, and kinetic aspects of the formation of coordination polymers

The reaction of ZnI2 and pyrimidine in acetonitrile results in the formation of the 1:2 compound ZnI2(pyrimidine)2 (1), which consists of discrete tetrahedral building blocks. Slow heating of 1 at 1 degrees C/min leads to its transformation into the ligand-deficient intermediate 1:1 compound ZnI2(pyrimidine) (3), which upon further heating decomposes into the most ligand-deficient 2:1 compound (ZnI2)2(pyrimidine) (4). In contrast, the 2:3 compound (ZnI2)2(pyrimidine)3 (2) is formed as an intermediate by decomposing 1 using a faster heating rate of 8 degrees C/min. Compound 2 consists of oligomeric units in which each ZnI2 unit is coordinated by two iodine atoms and one bridging and one terminal pyrimidine ligand. The crystal structure of compound 3 is built up of ZnI2 units, which are connected by the ligands into chains. For the thermal transformation of 1 into 3 via 2 as the intermediate, a smooth reaction pathway is found in the crystal structure, for which only small translational and rotational changes are needed. The metastable solvated compound (ZnI2)(pyrimidine)(acetonitrile)0.25 (5) consisting of (ZnI2)4(pyrimidine)4 rings is obtained by quenching the reaction of ZnI2 and pyrimidine in acetonitrile using an antisolvent. On heating, 5 decomposes into a new polymorphic 1:1 compound 6, which consists of (ZnI2)(pyrimidine) chains. On further heating, 6 transforms into a third polymorphic 1:1 compound 7, which consists of (ZnI2)3(pyrimidine)3 rings, and finally into the 1:1 compound 3. Solvent-mediated conversion experiments reveal that compounds 1-4 are thermodynamically stable, whereas compounds 5-7 are metastable. Time-dependent crystallization experiments unambiguously show that compound 7 is formed by kinetic control and transforms within minutes into compound 6, which finally transforms into 3. Compound 3 represents the thermodynamically most stable 1:1 modification, whereas compounds 6 and 7 are metastable. The different compounds obtained by thermal decomposition and by crystallization from solution represent a snapshot of the species in solution and thus provide insight into the formation of coordination compounds.     

Incorporation of water-soluble and water-insoluble ruthenium complexes into zirconium phosphate films fabricated by the layer-by-layer adsorption and reaction method

Water-soluble tris(2,2'-bipyridine)ruthenium(II) complex (Rubpy) and water-insoluble tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) complex (Rudpp) were successfully incorporated into zirconium phosphate (ZrPS) films fabricated by a facile layer-by-layer (LbL) adsorption and reaction method. Rubpy-incorporated ZrPS films were fabricated by the LbL adsorption and reaction method employing a mixture solution of Rubpy and phosphate salt. Rubpy was incorporated into ZrPS films during the formation of ZrPS layers because of the electrostatic interaction between them. Rudpp was dissolved in the mixture solution of aqueous phosphate salt and ethanol and was incorporated into ZrPS films through the formation of ethanol preintercalated ZrPS layers. The successful incorporation of Rubpy and Rudpp into ZrPS films was confirmed by UV-vis absorption spectroscopy. Rubpy and Rudpp have concentrations of 0.915 x 10 (14) and 3.23 x 10 (14) molecules/cm (2) in each ZrPS layer, respectively. Scanning electron microscopy measurements indicate that the as-prepared Rubpy-incorporated ZrPS films are smooth while the as-prepared Rudpp-incorporated ZrPS films are porous. The porous Rudpp-incorporated ZrPS films are suitable to use as oxygen sensors because the luminescence of Rudpp incorporated into the ZrPS films can be quenched by oxygen and the porous film structure facilitates the permeation of oxygen into and out of the film.     

元素在石墨炉内石墨探针表面上的原子化机理研究(X)——硝酸锶的原子化机理

用X射线衍射、X射线光电子能谱、俄歇电子能谱和扫描电子显微术等考察了石墨炉升温过程中Sr(NO₃)₂在石墨探针表面上的形态变化,阐明了它的原子化机理.加热过程中Sr(NO₃)₂首先分解为SrO(s),再还原为SrC₂,后者进一步分解为Sr(s).锶的原子化源于金属蒸发.     

CO2 reforming of CH4 on Ni(111): a density functional theory calculation

CO(2) reforming of CH(4) on Ni(111) was investigated by using density functional theory. On the basis of thermodynamic analyses, the first step is CH(4) sequential dissociation into surface CH (CH(4) --> CH(3) --> CH(2) --> CH) and hydrogen, and CO(2) dissociation into surface CO and O (CO(2) --> CO + O). The second step is CH oxygenation into CHO (CH + O --> CHO), which is more favored than dissociation into C and hydrogen (CH --> C + H). The third step is the dissociation of CHO into surface CO and H (CHO --> CO + H). This can explain the enhanced selectivity toward the formation of CO and H(2) on Ni catalysts. It is found that surface carbon formation by the Bouduard back reaction (2CO = C((ads)) + CO(2)) is more favored than by CH(4) sequential dehydrogenation. The major problem of CO(2) reforming of CH(4) is the very strong CO adsorption on Ni(111), which results in the accumulation of CO on the surface and hinders the subsequent reactions and promotes carbon deposition. Therefore, promoting CO desorption should maintain the reactivity and stability of Ni catalysts. The computed energy barriers of the most favorable elementary reaction identify the CH(4) activation into CH(3) and H as the rate-determining step of CO(2) reforming of CH(4) on Ni(111), in agreement with the isotopic experimental results.     

Highly stereocontrolled and regiocontrolled syntheses of 2,3,4-trisubstituted alkanoates and lactones

New chlorodiols (±)-3 and (±)-5 are densely functionalized and versatile synthons. They are converted in one step on a gram scale into 2-chlorolactones (±)-6 and (±)-7 and into 4-hydroxy glycidate esters (±)-9 and (±)-10. The 4-hydroxy glycidate esters (±)-9 and (±)-10 are converted stereospecifically and regiospecifically into oxazolines (±)-13 and (±)-14 and into cyclic carbamates (±)-18-(±)-20. The 4-hydroxy glycidate ester (±)-10 undergoes stereocontrolled and regiocontrolled epoxide opening by sodium azide to form the 2-azido-3,4-dihydroxy alkanoate (±)-21. Finally, chlorodiol (±)-5 reacts stereospecifically with silver triflate to form the 2,3-dihydroxyfuranone (±)-26.     

Totalsynthese von Betalainen

A total synthesis of betalaine pigments ( 6 ) is described. The key intermediate is betalamic acid in the form of its dimethyl ester semicarbazone ( 9 ), which was transformed with L-proline ( 16 ) into indicaxanthine dimenthl ester ( 5 ), with L-cyclodopa methul ester ( 17 ) into betanidine trimethyl ester ( 3 ) and by hydrolysis of the latter into betanidine ( 2 ).     

Theoretical studies on the reaction mechanism of palladium(0)-catalyzed addition of thiocyanates to alkynes

The reaction mechanism of the Pd(0)-catalyzed alkyne cyanothiolation reaction is investigated by MP2, CCSD(T) and the density functional method B3LYP. The overall reaction mechanism is examined. The B3LYP results are consistent with the results of CCSD(T) and MP2 methods for the isomerization, acetylene insertion and reductive elimination steps, but not for the oxidative addition step. For the oxidative addition, the bisphosphine and monophosphine pathways are competitive in B3LYP, while the bisphosphine one is preferred for CCSD(T) and MP2 methods. The electronic mechanisms for the oxidative addition of thiocyanate HS-CN to Pd(PH(3))(2) and Pd(PH(3)) and for the acetylene insertion into Pd-S and Pd-CN are discussed in terms of the electron-donation and back-donation. The chemo-selectivity that acetylene inserts into the Pd-S bond rather than into the Pd-CN bond is due to the involvement of the S p orbital. It is the doubly occupied S p unhybridized orbital that donates an electron to the alkylene pi* anti-bonding orbital, which makes insertion into Pd-S bond more favorable than into the Pd-CN bond. During the insertion into the Pd-S bond, the S sp(2) hybrid orbital and unhybridized p orbital transform into each other, while the C sp hybrid orbital shifts its direction for insertion into Pd-CN bond. By using the monosubstituted acetylenes (CN, Me and NH(2)), the influence of substituents at acetylene on the chemo- and regio-selectivities is analyzed.     

Penetration of bovine serum albumin into dipalmitoylphosphatidylglycerol monolayers: direct observation by atomic force microscopy

The penetration of bovine serum albumin (BSA) into dipalmitoylphosphatidylglycerol (DPPG) monolayers was observed using atomic force microscopy (AFM) and surface pressure measurements. The effects of surface pressure, amount of BSA and the addition of ganglioside GM1 (GM1) were investigated. The surface pressure of the DPPG monolayer was increased by the penetration of BSA, and the increase in surface pressure was greater in the liquid-expanded film than that in the liquid-condensed film. The AFM images indicated that BSA penetrated into the DPPG monolayer. The amount of BSA that penetrated into the DPPG monolayer increased with time and with the amount of BSA added. On the contrary, the AFM image showed that BSA penetration into the mixed DPPG/GM1 (9 : 1) monolayer scarcely occurred. GM1 inhibited the penetration of BSA into the DPPG monolayer.     

Effect of pH on the aluminum salts hydrolysis during coagulation process: formation and decomposition of polymeric aluminum species

Effect of pH on the aluminum chloride hydrolysis at low concentration was investigated in detail by electrospray ionization (ESI) mass spectrometry. In particular, formation and decomposition processes of polymeric aluminum species were discussed. When coagulant AlCl(3) was diluted to normal coagulant dose (1.5 x 10(-4) mol/L), hydrolysis occurred immediately. Monomeric and dimeric aluminum species were the main products at pH 4.0. With pH increasing, hydrolysis and polymerization processes were accelerated. Monomeric and dimeric aluminum species hydrolyzed and polymerized into small polymeric aluminum species (Al(3)-Al(5) species) at pH 4.8. Through aggregation and self-assembly, the small polymeric aluminum species polymerized into median polymeric species (Al(6)-Al(10) species) at pH 5.0. In the same way, small and median polymeric aluminum species further aggregated into large polymeric species (Al(11)-Al(21) species). When pH was up to 5.8, metastable median and large polymers species decomposed into small aluminum species, then further disaggregated into dimeric species. With pH increased to 6.4, majority of aluminum species formed to Al(OH)(3) amorphous flocs. Accordingly, coagulant hydrolysis mechanism from polymerization toward decomposition was proposed. Furthermore, formation and decomposition of polymeric aluminum species in AlCl(3) solution followed the "Core-links" model, while those of Keggin-Al(13) species in polyaluminum solution was based on the "Cage-like" model.     

Application of computer simulation free-energy methods to compute the free energy of micellization as a function of micelle composition. 2. Implementation

In this paper, the implementation of the CS-FE/MT model introduced in article 1 is discussed, and computer simulations are performed to evaluate the feasibility of the new theoretical approach. As discussed in article 1, making predictions of surfactant/solubilizate aqueous solution behavior using the CS-FE/MT model requires evaluation of DeltaDeltaG for multiple surfactant-to-solubilizate or surfactant-to-cosurfactant transformations. The central goal of this article is to evaluate the quantitative accuracy of the alchemical computer simulation method used in the CS-FE/MT modeling approach to predict DeltaDeltaG for a single surfactant-to-solubilizate or for a single surfactant-to-cosurfactant transformation. A hybrid single/dual topology approach was used to morph the ionic surfactant sodium dodecyl sulfate (SDS) into the ionic solubilizate ibuprofen (IBU), and a dual topology approach was used to morph the nonionic surfactant octyl glucoside (OG) into the nonionic solubilizate p-aminobenzoate (PAB). In addition, a single topology approach was used to morph the nonionic surfactant n-decyl dimethylphosphine oxide (C10PO) into the nonionic cosurfactant n-decyl methyl sulfoxide (C10SO), the nonionic surfactant octylsulfinyl ethanol (C8SE) into the nonionic cosurfactant decylsulfinyl ethanol (C10SE), and the nonionic surfactant n-decyl methyl sulfoxide (C10SO) into the nonionic cosurfactant n-octyl methyl sulfoxide (C8SO). Each DeltaDeltaG value was computed by using thermodynamic integration to determine the difference in free energy associated with (i) transforming a surfactant molecule of type A into a cosurfactant/solubilizate molecule of type B in a micellar environment (referred to as DeltaG2) and (ii) transforming a surfactant molecule of type A into a cosurfactant/solubilizate molecule of type B in aqueous solution (referred to as DeltaG1). CS-FE/MT model predictions of DeltaDeltaG for each alchemical transformation were made at a number of simulation conditions, including (i) different equilibration times at each value of the coupling parameter lambda, (ii) different data-gathering times at each lambda value, and (iii) simulation at a different number of lambda values. For the three surfactant-to-cosurfactant transformations considered here, the DeltaDeltaG values predicted by the CS-FE/MT model were compared with DeltaDeltaG values predicted by an accurate molecular thermodynamic (MT) model developed by fitting to experimental CMC data. Even after performing lengthy equilibration and data gathering at each lambda value, physically unrealistic values of DeltaDeltaG were predicted by the CS-FE/MT model for the transformations of SDS into IBU and of OG into PAB. However, more physically realistic DeltaDeltaG values were predicted for the transformation of C10PO into C10SO, and reasonable free-energy predictions were obtained for the transformations of C8SE into C10SE and C10SO into C8SO. Each of the surfactant-to-cosurfactant transformations considered here involved less extensive structural changes than the surfactant-to-solubilizate transformations. As computer power increases and as improvements are made to alchemical free-energy methods, it may become possible to apply the CS-FE/MT model to make accurate predictions of the free-energy changes associated with forming multicomponent surfactant and solubilizate micelles in aqueous solution where the chemical structures of the surfactants, cosurfactants, and solubilizates differ significantly.     

Unsuccessful/successful attempts to produce penta(heteroaryl)-phosphoranes/-arsoranes R5E (E = P, As; R = 2-furyl, 2-thienyl)

Tri(2-thienyl)phosphine (1) has been transformed into chlorotri(2-thienyl)phosphonium chloride (3) in the reaction with hexachloroethane, into tetra(2-thienyl)phosphonium bromide (4) in a NiBr2-catalyzed quaternization with 2-bromothiophene, and into the p-tolylsulfonyliminotri(2-thienyl)phosphorane (6) using "chloramine T". Attempts to generate the homoleptic penta(2-thienyl)phosphorane (2-C4H3S)5P (5) by treating 3, 4, 6 or the known (PhO)3P=NSO2C6H4-2-Me (9) with 2-thienyllithium were unsuccessful. Tri(2-furyl)phosphine (2) was converted into the related imine 7, but the reaction of 7 or of 9 with 2-furyllithium failed to give (2-C4H3O)5P (8). It was only with the strained phosphorane Ph(C12H8)P=NSO2C6H4-4-Me (C12H8= 2,2'-biphenylylene) (10) that with 2-C4H3OLi the corresponding phosphorane Ph(C12H8)P(C4H3O-2)2 (11) could be obtained (31P NMR: delta-106.7 ppm). In the arsenic series, tri(2-thienyl)- and tri(2-furyl)arsine (12, 13) were converted into the tosylimino compounds (14, 15) and successfully transformed into the homoleptic arsoranes with 2-C4H3E-Li: penta(2-thienyl)- (16) and penta(2-furyl)-arsorane (17) are stable colourless crystalline solids, the NMR spectra of which indicate rapid pseudo-rotation in solution. The single crystal structure analysis of 17 shows an only slightly distorted trigonal-bipyramidal configuration. In crystals of the phosphine 2 and the arsine 13 the molecules have a propeller configuration with approximate C3v symmetry for the former, but Cs symmetry for the latter. The crystal structures of the precursors or intermediates 3, 4, 6, 9, and 10 have also been determined.     

Chlorination of Irgasan DP300 and formation of dioxins from its chlorinated derivatives

Irgasan DP300 (2,4,4'-trichloro-2'-hydroxydiphenyl ether) (I), an antimicrobial agent for use with fabrics, was easily chlorinated with sodium hypochlorite to give 2',3,4,4'-tetrachloro-2-hydroxydiphenyl ether (II), 2',4,4',5-tetrachloro-2-hydroxydiphenyl ether (III) and 2',3,4,4',5-pentachloro-2-hydroxydiphenyl ether (IV). Irgasan DP300 and its chlorinated derivatives were readily converted into polychlorinated dibenzo-p-dioxins (PCDDs) by heating: Irgasan DP300 was converted into dichlorodibenzo-p-dioxin(s) (di-CDD, 42%); II into two trichlorodibenzo-p-dioxins (tri-CDDs, 22%) and three tetrachlorodibenzo-p-dioxins (tetra-CDDs, 46%); III into two tri-CDDs (44%), more than two tetra-CDDs (25%) and pentachlorodibenzo-p-dioxin(s) (penta-CDD, 1%); and IV into two tetra-CDDs (16%), trace amounts of penta-CDD(s) and four hexachlorodibenzo-p-dioxins (hexa-CDDs, 40%). Although UV irradiation of Irgasan DP300, II and III gave PCDDs, the amounts of PCDDs formed were much smaller than those obtained by heating. Moreover, PCDD was not detected in the UV irradiation of IV. The identified products suggested that disproportionation of chlorine atom(s) occurred in the photolysis.     

Electrooxidation of alken-1-ylarenes in aqueous alcohol solutions

In the initial stages of the electrooxidation of alken-1-ylarenes-propenyl-benzene (Ia) and 4-propenylanisole (Ib)- in aqueous alcohol solutions, 1,2-dialkoxypropyl- (II), 1-hydroxy-2-alkoxypropyl- (VII), and 1,2-dihydroxy-propyl arenes (VIII) are formed. Subsequent rupture of the C-C benzyl bond converts the ethers (II) into benzaldehyde acetals (III) and benzaldehydes (IV), and compounds (VII) and (VIII) into (IV). Benzaldehydes (IV) are also formed from (II) by hydrolysis of the acetals (III)- partly for (IIIa) and completely for (IIIb). Electrolysis of (Ia and Ib) in aqueous alcohol solution leads mainly to their conversion into benzaldehydes (IV).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2356–2361, October, 1991.     

Zinc and cadmium 2-pyrazinephosphonates: syntheses, structures and luminescent properties

Three new metal(II) 2-pyrazinephosphonates have been synthesized by hydrothermal reactions based on 2-pyrazinephosphonic acid (C(4)H(3)N(2)PO(3)H(2)1) as ligand, namely, Zn(C(4)H(3)N(2)PO(3)) (2), Cd[(C(4)H(3)N(2)PO(3))(H(2)O)] (3) and Cd[(C(4)H(3)N(2)PO(3)H)Cl]·H(2)O (4). In compound 2, the O-P-O bridged inorganic layers are pillared by pyrazinyl groups into a three-dimensional network. In compound 3, the {CdO(5)N} and {CPO(3)} polyhedra are interconnected via edge and corner-sharing into a metal phosphonate layer. In compound 4, the {Cd(2)Cl(2)} dimers are linked by O-P-O bridges into a one-dimensional double chain, and the chains are joined into a layer by pyrazinyl groups. Here we employ pyrazinephosphonic acids as structure directing motifs to form extended structures and materials with interesting luminescent properties. The luminescent properties studied have also been described.     

3-Carboxypyridinium Dichromate (NDC) and (4-Carboxypyridinium Dichromate (INDC). Two New Mild,Stable, Efficient,and Inexpensive Chromium (VI) Oxidation Reagents

Two mild new chromium (VI) reagents derived from nicotinic acid and isonicotinic acid are described. Nicotinium dichromate (NDC) and isonicotinium dichromate (INDC) oxidize alcohols into carbonyl compounds, mercaptans into disulfides and hydroquinones into quinones. Oxidtion of polynuclear aromatic hydrocarbons is made. Pyridine assisted oxidations by means of these reagents are also described.     

Novel synthesis of cis-3,5-disubstituted morpholine derivatives

1-tert-Butyl-2-(allyloxymethyl)aziridine has been transformed for the first time diastereoselectively into cis-3,5-di(bromomethyl)-4-tert-butylmorpholine via an electrophile-induced ring closure using bromine in dichloromethane. The latter morpholine has been used as a substrate for the synthesis of the corresponding 3,5-di(methoxymethyl)morpholine and 3,5-di(cyanomethyl)morpholine upon nucleophilic displacement of both bromo atoms. Further evaluation of this protocol toward the synthesis of 4-arylmethyl- and 4-alkylmethyl-3,5-di(bromomethyl)morpholines showed that the premised cyclization of the corresponding 2-(allyloxymethyl)aziridines into 3,5-di(bromomethyl)morpholines only proceeded well for the N-neopentylmorpholine, which was subsequently transformed into a 3-oxa-7-thia-9-azabicyclo[3.3.1]nonane derivative. Also, in some other cases, the desired 3,5-di(bromomethyl)morpholines were isolated in low yields and transformed into the corresponding 3,5-di(cyanomethyl)morpholines.     

Morphology transformation via pH-triggered self-assembly of peptides

Three flexible peptides (P1: (C(17)H(35)CO-NH-GRGDG)(2)KG; P2: (Fmoc-GRGDG)(2)KG; P3: (CH(3)CO-NH-GRGDG)(2)KG) self-assembled to form a variety of morphologically distinct assemblies at different pHs. P1 formed nanofibers at pH 3, then self-assembled into nanospheres with pH up to 6 and further changed to lamellar structures when the pH value was further increased to 10. P2 aggregated into an entwined network structure at pH 3, and then self-assembled into well-defined nanospheres, lamellar structures, and vesicles via adjusting the pH value. However, P3 did not self-assemble into well-ordered nanostructures, presumably due to the absence of a large hydrophobic group. The varying self-assembly behaviors of the peptides at different pHs are attributed to molecular conformational changes. These self-assembled supramolecular materials might contribute to the development of new peptide-based biomaterials.     

Effects of Y (Ⅲ) Ions on the Fluorescence Properties of Ce(Ⅲ) Ion and the Organic Ligands in the Complex

The enhancement effects of Y ( Ⅲ) ions on the fluorescence of Ce ( Ⅲ) in Ce ( Ⅲ)-Y ( Ⅲ)-PMMA (polymethylmethacrylate ) or Ce ( Ⅲ)-Y ( Ⅲ)-PVC (polyvinyl chloride ) complex systems were observed. The influence of Y ( Ⅲ) ions on the emission spectra of PMMA ligands in PMMA-Y ( Ⅲ) and the fluorescent enhance- ment of Y( Ⅲ) on Ce( Ⅲ) emission in PMMA-Ce-Y by Y( Ⅲ) ion were studied. It was also of interest to note that when Y ( Ⅲ) ions were added into PMMA and into bpy(bipyridine ), respectively, the emission spectrum of PMMA ligands was split into fine structure bands by Y ( Ⅲ), and the fluorescence intensities of bpy ligands in bpy-Y ( Ⅲ) complexes were considerably increased.     

Evidence of intercalation of trans-diethylstilbestrol and its methyl ether derivatives in multibilayers of egg phosphatidylcholine by high-power deuterium nuclear magnetic resonance (2H-NMR) spectroscopy

The mode of incorporation of 2H-labeled trans-diethylstilbestrol (DES) (1b) and its methyl ether derivatives (2a, 2b, and 3) into multibilayers of egg phosphatidylcholine was analyzed by means of deuterium nuclear magnetic resonance. A clear distinction was found between DES or its methyl ether derivatives incorporated into lipid bilayers and those precipitated in the aqueous phase, by taking into account the extent of the motionally averaged quadrupole interaction. Thus, it was found that the relative proportion of these compounds incorporated into multibilayers decreased in the following order: DES (1b) greater than DES monomethyl ether (2a and 2b) greater than DES dimethyl ether (3). In addition, we demonstrated that the mode of intercalation in the multibilayers differs greatly among these compounds.