Submit to Crystals Review for Crystals Edit a Special Issue

Journal Menu

Journal Browser

► Journal Browser

Special Issue "Crystal Structure Analysis of Supramolecular and Porous Solids"

Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Macromolecular Crystals".

Deadline for manuscript submissions: closed (31 December 2017) | Viewed by 47937

Share This Special Issue

Special Issue Editor

Prof. Dr. Dmitriy V Soldatov

E-Mail Website
Guest Editor

Department of Chemistry, University of Guelph, Guelph, Canada
Interests: supramolecular and nanoporous materials; molecular crystals and cocrystals; natural and synthetic polymers; self-assembly and crystal engineering; reactivity in the solid state
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Supramolecular chemistry emerged as a powerful tool for chemists to create new materials from already known molecules. In a supramolecular solid, dissimilar molecules complement each other to build a new, highly organized structure, as seen in host–guest complexes, inclusion compounds, pharmaceutical co-crystals, supramolecular polymers, biomimetic materials, or mechanically interlocked molecular assemblies.

Supramolecular solids are a new target in materials science, where desired properties in a material can be predicted and generated through a specific arrangement of the molecules in the 3D structure. A range of physical (e.g., optical, electrical, magnetic), chemical (thermal stability, reactivity, catalysis) and biomedical (toxicity, bioavailability) properties have been created or tuned in various solids using this approach known as crystal engineering.

Porous solids, with uniform pores on molecular or nano scale, are produced from supramolecular solids. In the first step of this production, a guest template is used to shape a desired topology of pores with specific sorption, catalytic or ion-exchange capabilities. At a later stage, the guest template is removed to yield a zeolite, mesoporous silica, porous metal organic framework material, or porous material based on weaker interactions.

Crystal structure analysis is a primary characterization method in the design and study of supramolecular and porous solids. It provides the most critical information about the spatial arrangement of molecules in the crystal, topology and geometry of the cavity space, intermolecular interactions, as well as any changes in the structure induced by temperature, pressure or guest inclusion/removal. This Special Issue deals with all aspects of such research. The topics include, but are not limited to:

Design of new host molecules and host materials
Preparation and characterization of inclusion compounds
Design and characterization of co-crystals
Design of porous frameworks
Studies on weak intermolecular interactions in supramolecular solids
Studies on molecular disorder and dynamics in molecular crystals
Structural studies of phase transitions in supramolecular and porous solids
Database studies on supramolecular and porous solids

Prof. Dr. Dmitriy V Soldatov
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Crystals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

supramolecular chemistry
crystal engineering
inclusion compounds
clathrates
cocrystals
metal organic frameworks
covalent organic frameworks
hydrogen-bonded organic frameworks
nanoporous materials
organic zeolites
pseudopolymorphism
phase transitions in crystals

Published Papers (13 papers)

Download All Papers

Research

Open AccessArticle

Synthesis and Crystal Structures of Cadmium(II) Cyanide with Branched-Butoxyethanol

Takeshi Kawasaki

and

Takafumi Kitazawa

Crystals 2018, 8(5), 221; https://doi.org/10.3390/cryst8050221 - 17 May 2018

Cited by 2 | Viewed by 2764

Abstract

Two novel 3D cadmium(II) cyanide coordination polymers with branched-butoxyethanol compounds (iBucel = iso-butoxyethanol, tBucel = tert-butoxyethanol), [{Cd(CN)₂(iBucel)₂}{Cd(CN)₂(H₂O)(iBucel)}₂{Cd(CN)₂}₆∙2(iBucel)]_n I and [{Cd(CN)₂(H₂O)_1.06(tBucel)_0.94}{Cd(CN)₂(tBucel)}₂{Cd(CN)₂}₂∙1.06(tBucel)]_n II, were synthesized and characterized by structural determination. Complex I contains two distinct Cd(II) coordination geometries: octahedral and tetrahedral. In contrast, complex II contains three distinct Cd(II) coordination geometries: octahedral, square-pyramidal, and tetrahedral. In the two complexes, branched-butoxyethanol molecules behave as both a ligand and a guest in the Cd(CN)₂ cavities. The framework in I contains octahedral and tetrahedral Cd(II) in a 3:6 ratio. In I, the coordination environments of octahedral Cd(II) are cis-O-Cd-O. The framework in II contains octahedral, square-pyramidal, and tetrahedral Cd(II) in a 1:2:2 ratio. In II, the coordination environment of octahedral Cd(II) is disordered trans-O-Cd-O and the axial oxygen ligand is either a water or tBucel molecule. In II, the square-pyramidal Cd(II) geometry is formed by one tBucel ligand and four cyanide ligands. The Cd(CN)₂ frameworks of the two complexes exhibit different structures. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessEditor’s ChoiceArticle

Tuning of Luminescent and Magnetic Properties via Metal Doping of Zn-BTC Systems

and

Crystals 2018, 8(4), 162; https://doi.org/10.3390/cryst8040162 - 08 Apr 2018

Cited by 7 | Viewed by 4818

Abstract

In order to assess how metal doping affects the luminescence and magnetic properties of anionic Metal-Organic Frameworks (MOFs), seven single-metal doped MOFs {M-Zn-BTC}{Me₂NH₂⁺} (M = Co, Cu, Ni, Mn, Ca, Mg, Cd) and three dual-metal doped MOFs {Zn-M₁-M₂-BTC}{Me₂NH₂⁺} (M₁ = Co, Cu; M₂ = Ni, Co) were synthesized. Trace amounts of different metals were doped via addition of another metal salt during the synthetic process. All compounds retained the same crystal structure as that of the parent {Zn-BTC}{Me₂NH₂⁺} MOF, which was supported by single crystal and powder X-ray diffraction studies. Thermal Gravimetric Analysis (TGA) of these compounds also revealed that all MOFs had similar stability up to ~450 °C. Solid state photoluminescent studies indicated that {Zn-Mn-BTC}{Me₂NH₂⁺}, {Zn-Cd-BTC}{Me₂NH₂⁺}, and {Zn-Ca-BTC}{Me₂NH₂⁺} had a significant red shifting effect compared to the original {Zn-BTC}{Me₂NH₂⁺} MOF. Applications of this doping method to other MOF systems can provide an efficient way to tune the luminescence of such systems, and to obtain a desired wavelength for several applications such as sensors and white light LED materials. Because Zn, Co, Cu, Ni, Mg have magnetic properties, the effect of the doping metal atom on the magnetism of the {Zn-BTC}{Me₂NH₂⁺} networks was also studied. To characterize the magnetic behavior of the synthesized MOFs, we conducted low-temperature (10 K) saturation remanence experiments in a 3 Tesla applied field, with the principal goal of identifying the domain state of the synthesized materials (Zn, Zn-Co, Zn-Cu-Co, Zn-Cu-Ni, Zn-Mg, Zn-Mn, Zn-Ni-Co, Zn-Ni). During room/low temperature saturation magnetization experiments, Zn, Zn-Co, Zn-Cu-Co, and Zn-Cu-Ni systems yielded data indicative of superparamagnetic behavior, yet during zero field and field cooled experiments Zn-Co showed a slight paramagnetic effect, Zn showed no temperature dependence on warming and Zn-Cu-Co and Zn-Cu-Ni demonstrated only a slight temperature dependence on warming. These behaviors are consistent with ferromagnetic ordering. Zero field and field cooled experiments indicate that Zn-Mg and Zn-Ni have a ferromagnetic ordering and Zn-Mn and Zn-Ni-Co show paramagnetic ordering behavior. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Structure and Magnetic Properties of a 1D Alternating Cu(II) Monomer―Paddlewheel Chain

Vanessa Machado

Mark M. Turnbull

and

Louise N. Dawe

Crystals 2018, 8(3), 114; https://doi.org/10.3390/cryst8030114 - 28 Feb 2018

Cited by 6 | Viewed by 3746

Abstract

One-dimensional metal–organic coordination polymers make up a class of compounds with potential towards the development of practical, new magnetic materials. Herein, a rare example of an ABBABB coupled linear chain comprised of alternating dicopper(II) tetraacetate units bridged to copper(II) acetate monomer units via axial η²:η¹:µ₂ coordinated acetate is reported. Examination of the structure, determined by small molecule X-ray crystallography, shows that each Cu(II) ion is in a d_x2–_y2 magnetic ground state. Magnetic susceptibility and magnetization data were collected and, consistent with the structural interpretation, demonstrate that the Cu(II) dimer (paddlewheel) exhibits classic antiferromagnetic exchange, while the S = 1/2 Cu(II) monomer is uncompensated in the ground state (low temperature regime.) Data were therefore fitted to a modified Bleaney-Bowers model, and results were consistent with the only other reported chain in this class for which magnetic data are available. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessArticle

Incorporation of Hexanuclear Mn(II,III) Carboxylate Clusters with a {Mn₆O₂} Core in Polymeric Structures

and

Crystals 2018, 8(2), 100; https://doi.org/10.3390/cryst8020100 - 17 Feb 2018

Cited by 3 | Viewed by 3366

Abstract

A new series of hexanuclear mixed-valent carboxylate coordination clusters of the type [Mn6O2(O2CR)10L4] (R = CMe3; CHMe2) featuring a {MnII4MnIII2(μ4-O)2} core of composition [Mn6O2(O2CCMe3)10(Me3CCO2H)3(EtOH)]•(Me3CCO2H) (1), [Mn6O2(O2CCMe3)10(Me3CCO2H)2 (EtOH)2]•2(EtOH) (2) and [Mn6O2(O2CCMe3)10(Me3CCO2H)2(MeOH)2]•2(MeOH)•H2O (3), and coordination polymers which incorporate such clusters, namely [Mn6O2(O2CCHMe2)10(pyz)(MeOH)2]n (4), {[Mn6O2(O2CCHMe2)10(pyz)1.5(H2O)]•0.5(H2O)}n (5), and [Mn6O2(O2CCMe3)10(HO2CCMe3)2(en)]n (6), have been synthesized (where pyz = pyrazine, en = ethyl nicotinate). The modification of the cluster surface by a diverse combination of capped or bridging ligands attached to peripheral MnII atoms results in discrete clusters with a closed hydrophobic exterior shell in 1 and 2, supramolecular chains built through hydrogen bonded solvent molecule clusters in 3, linear coordination polymers in 4 and 6 or a ladder-like coordination polymer in 5. The H-bonded coordination polymers 4 and 5 form supramolecular layers in crystals. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessArticle

A Standard Structure for Bile Acids and Derivatives

María Pilar Vázquez-Tato

Francisco Fraga

and

José Vázquez Tato

Crystals 2018, 8(2), 86; https://doi.org/10.3390/cryst8020086 - 06 Feb 2018

Cited by 5 | Viewed by 3852

Abstract

The crystal structures of two ester compounds (a monomer in its methyl ester form, with an amino isophthalic group, and a dimer in which the two steroid units are linked by a urea bridge recrystallized from ethyl acetate/methanol) derived from cholic acid are described. Average bond lengths and bond angles from the crystal structures of 26 monomers and four dimers (some of them in several solvents) of bile acids and esters (and derivatives) are used for proposing a standard steroid nucleus. The hydrogen bond network and conformation of the lateral chain are also discussed. This standard structure was used to compare with the structures of both progesterone and cholesterol. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Effect of Sorbitol Templates on the Preferential Crystallographic Growth of Isotactic Polypropylene Wax

Zoe V. Quiñones-Jurado

Carlos A. Ávila-Orta

Blanca E. Castillo-Reyes

José M. Mata-Padilla

Benjamin S. Hsiao

Francisco J. Medellín-Rodríguez

and

Miguel A. Waldo-Mendoza

Crystals 2018, 8(2), 59; https://doi.org/10.3390/cryst8020059 - 26 Jan 2018

Cited by 3 | Viewed by 3271

Abstract

The crystallization of isotactic polypropylene wax (iPP) in the presence of different sorbitol structures was studied. Dibenzylidene Sorbitol (DBS), as well as two of its derivatives with one or two methyl groups in the DBS molecule (MDBS and DMDBS, respectively), were tested as nanometer-size fibrillar templates. The early nucleation stage and crystal morphology were analyzed in Real-Time Wide-Angle X-ray Scattering (WAXS) and polarized optical microscopy (POM). It was found that the iPP crystals showed an α-phase unit cell for the three different sorbitols. However, a preferential crystal growth in the plane (040) was observed for iPP–MDBS. The macrostructure morphology of the iPP–DBS and iPP–DMDBS wax compounds was spherulitic, while nodular macrocrystals were observed for the iPP–MDBS compound. It was concluded that the MDBS template promoted a lower interface energy because of its match with the c-axis of the iPP wax crystals, whereas, in the case of the DBS and DMDBS templates, the preferential plane was the (110), characteristic of the iPP spherulitic arrangement. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Conductive Supramolecular Architecture Constructed from Polyoxovanadate Cluster and Heterocyclic Surfactant

and

Crystals 2018, 8(2), 57; https://doi.org/10.3390/cryst8020057 - 25 Jan 2018

Cited by 5 | Viewed by 2778

Abstract

Proton-conductive solid electrolytes are significant for fuel-cell battery technology. Especially for use in motor vehicles, proton conductors which work at intermediate temperatures (373–673 K) under an anhydrous atmosphere are desired to improve the fuel cell stability and efficiency. Inorganic–organic hybrid supramolecular architectures are a promising option for the realization of highly conductive proton conductors. Here, a hybrid layered crystal was synthesized for the first time by using an proton-containing decavanadate (V₁₀) anion and a heterocyclic surfactant cation. A simple ion-exchange reaction led to the formation of an inorganic–organic hybrid of V₁₀ by using dodecylpyridazinium (C₁₂pda) as the heterocyclic surfactant. Single crystal X-ray analyses revealed that four C₁₂pda cations were associated with one V₁₀ anion, which was a diprotonated species forming a one-dimensional infinite chain structure through hydrogen bonds. Anhydrous proton conductivity was investigated by alternating current (AC) impedance spectroscopy in the range of 313–393 K, exhibiting a maximum value of 1.7 × 10⁻⁵ S cm⁻¹ at 373 K. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Two Supramolecular Inorganic–Organic Hybrid Crystals Based on Keggin Polyoxometalates and Crown Ethers

, Shao-Fang Lv,

and

Crystals 2018, 8(2), 17; https://doi.org/10.3390/cryst8020017 - 23 Jan 2018

Cited by 9 | Viewed by 3735

Abstract

New supramolecular structures were designed in this work using large-sized polyoxometalates (POMs) and crown-ether-based supramolecular cations selected as building blocks. Two novel supramolecular inorganic–organic hybrids [(3-F-4-MeAnis)([18]crown-6)]₂[SMo₁₂O₄₀]•CH₃CN (1) and [(4-IAnis)([18]crown-6)]₃[PMo₁₂O₄₀]•4CH₃CN (2) (3-F-4-MeAnis = 3-fluoro-4-methylanilinium and 4-IAnis = 4-iodoanilinium) were synthesized. Crystals 1 and 2 have been characterized by infrared spectroscopy (IR) and elemental analysis (EA). Based on X-ray diffraction analysis, Crystals 1 and 2 were constructed through noncovalent bonding interactions and belong to different space groups due to the difference of the building blocks used. Supramolecular cations formed due to strong N–H···O hydrogen bonding interactions between the six oxygen atoms of [18]crown-6 molecules and nitrogen atoms of anilinium derivatives. Crystal 1 has two different supramolecular cations with an anti-paralleled arrangement that forms a dimer through weak hydrogen bonding interactions between adjacent [18]crown-6 molecules. Crystal 2 has three independent supramolecular cations that fill large spaces between the [PMo₁₂O₄₀] polyoxoanions forming a rhombus-shape packing arrangement in the ac plane. Crystals 1 and 2 are unstable at room temperature. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessArticle

Salts and Co-Crystalline Assemblies of Tetra(4-Pyridyl)Ethylene with Di-Carboxylic Acids

Moustafa T. Gabr

and

F. Christopher Pigge

Crystals 2018, 8(1), 41; https://doi.org/10.3390/cryst8010041 - 17 Jan 2018

Cited by 1 | Viewed by 3953

Abstract

Tetraarylethylene derivatives are emerging as an increasingly important family of supramolecular building blocks in both solution phase and the solid state. The utility of tetraarylethylenes stems from appealing structural features (rigidity and symmetry) and their propensity to exhibit aggregation induced emission (AIE). In an effort to investigate the luminescent sensing ability of heteroaromatic tetraarylethylenes, we previously prepared tetra(4-pyridyl)ethylene and characterized its solution phase AIE properties. We here report the successful incorporation of tetra(4-pyridyl)ethylene into three distinct salts and co-crystalline assemblies with three organic di-carboxylic acids (oxalic acid, malonic acid, and fumaric acid). Interactions between the tetra(pyridyl)ethylene and di-acid components were found to vary from conventional to charge-assisted hydrogen bonding according to the extent of proton transfer between the acid and pyridine groups. Notably, the formation of pyridinium-carboxylate adducts in the salts does not appear to be strongly correlated with acid pKa. Three distinct network topologies were observed, and all featured the bridging of two or three tetra(pyridyl)ethylene groups through di-acid linkers. Crystalline assemblies also retained the AIE activity of tetra(pyridyl)ethylene and were luminescent under UV light. As tetra(4-pyridyl)ethylene features four Lewis basic and potentially metal ligating pyridine rings in a relatively well-defined geometry, this compound represents an attractive building block for the design of additional crystalline organic and metal–organic functional materials. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessArticle

A Robust Framework Based on Polymeric Octamolybdate Anions and Copper(II) Complexes of Tetradentate N-donor Ligands

and

Juan M. Gutiérrez-Zorrilla

Crystals 2018, 8(1), 20; https://doi.org/10.3390/cryst8010020 - 06 Jan 2018

Cited by 7 | Viewed by 3858

Abstract

A new organic-inorganic compound based on octamolybdate building blocks and copper(II) complexes of tetradentate N-donor ligands has been hydrothermally synthesized, namely [Cu(cyclam)]₂[Mo₈O₂₆]·1.5H₂O (1), (cyclam: 1,4,8,11–tetraazacyclotetradecane). Compound 1 has been chemically (elemental and thermal analyses), spectroscopically (infrared spectroscopy), and structurally (single crystal and powder X-ray diffraction) characterized. The crystal packing of 1 shows a covalent framework structure formed by [Mo₈O₂₆]_n⁴ⁿ⁻ chains running along the 100 direction which are linked to each other through the coordination spheres of {Cu(cyclam)}²⁺ complexes leading to a three-dimensional open network. This structural assembly generates voids that can be described as a succession of cavities communicated through narrow bottlenecks with approximate cross section of 4 × 7 Å² where the hydration water molecules are hosted. The robust open structure of 1 remains virtually unaltered upon thermal evacuation of guest solvent molecules at 130 °C, resulting in the anhydrous phase [Cu(cyclam)]₂[Mo₈O₂₆] (1a) with potentially accessible micropores as demonstrated by single-crystal X-ray diffraction measurements. Electron paramagnetic resonance spectroscopy analysis of 1 has also been assessed. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Synthesis and Luminescence Properties of New Metal-Organic Frameworks Based on Zinc(II) Ions and 2,5-Thiophendicarboxylate Ligands

and

Crystals 2018, 8(1), 7; https://doi.org/10.3390/cryst8010007 - 24 Dec 2017

Cited by 9 | Viewed by 3858

Abstract

Six new metal-organic frameworks based on 2,5-thiophendicarboxylate (tdc^2–) and zinc(II) ions were prepared in different reaction conditions, and their crystal structures were determined by XRD analysis. The compound [Zn(tdc)(dabco)(H₂O)]∙DMF (1) is based on mononuclear Zn(II) ions connected by tdc^2– and dabco linkers into square-grid layered nets. The compound [Zn₃(tdc)₃(dabco)₂] (2) is a rare example of monocoordinated dabco ligands in the metal-organic framework chemistry. Its crystal structure contains trinuclear linear carboxylate building units, connected into a distorted primitive cubic net. Similar trinuclear units were also found in [Zn₅(tdc)₄(Htdc)₂(dabco)₂]∙4DMF∙14H₂O (3), although as a part of more complicated pentanuclear motives. The compound [Na₂Zn(tdc)₂(DMF)₂] (4), quantitatively isolated by the addition of NaOH to the mixture of Zn(NO₃)₂ and H₂tdc, is based on 1D chain motives, interconnected by tdc^2– linkers into a three-dimensional framework. The compounds [Zn₃(tdc)₃(DMF)₂]∙0.8DMF∙1.1H₂O (5) and [Zn₃(tdc)₃(DMF)₃]∙0.8DMF∙1.3H₂O (6) were prepared in very similar reaction conditions, but with different times of heating, indirectly indicating higher thermodynamic stability of the three-dimensional metal-organic framework 6, compared to the two-dimensional metal-organic framework 5. The crystal structures of both 5 and 6 are based on the same trinuclear linear units as in 2. Luminescence properties of the compounds 4–6 were studied and compared with those for Na₂tdc salt. In particular, the luminescence spectra of 4 practically coincide with those for the reference Na₂tdc, while 5 and 6 exhibit coherent shifts of peaks to higher energies. Such hypsochromic shifts are likely associated with a different effective charge on the tdc^2– anions in Na₂tdc and sodium-containing 4, compared to zinc-based 5 and 6. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Graphical abstract

Open AccessArticle

Breathing 3D Frameworks with T-Shaped Connecting Ligand Exhibiting Solvent Induction, Metal Ions Effect and Luminescent Properties

and

Crystals 2017, 7(10), 311; https://doi.org/10.3390/cryst7100311 - 17 Oct 2017

Cited by 2 | Viewed by 3863

Abstract

To study the structural effects in three-dimensional porous coordination polymers, three novel flexible porous coordination polymers—[Cd₂(bpdc)₂](DMF)₃(H₂O) (1) and [M(bpdc)](DMF)(H₂O) (M = Cd (2), Zn (3))—have been synthesized under solvothermal conditions with d¹⁰ block metal ions and T-shaped connecting ligand. Complexes 1–3 crystallize in different space groups, but they display the same ant network. The first two complexes can transform into each other via the alteration of guest, whereas complex 3 shows no structural change. The structural details reveal that the size of metal ions might be responsible for the transformation of porous frameworks. Furthermore, luminescent properties have been explored, and a guest-dependent shift of emission peaks was observed, suggesting potential application of the complexes as a probe. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Open AccessArticle

Substituent Effects on the Crystal Structures of Salts Prepared from (R)-2-Methoxy-2-(1-naphthyl)propanoic Acid and (R)-1-Arylethylamines

Akio Ichikawa

Hiroshi Ono

and

Yuji Mikata

Crystals 2017, 7(9), 263; https://doi.org/10.3390/cryst7090263 - 28 Aug 2017

Cited by 1 | Viewed by 3410

Abstract

The crystal structures of salts 6–9 prepared from (R)-2-methoxy-2-(1-naphthyl)propanoic acid [(R)-MαNP acid, (R)-1] and (R)-1-arylethylamines [salt 6, (R)-1-(4-methoxyphenyl)ethylamine∙(R)-1; salt 7, (R)-1-(4-fluorophenyl)ethylamine∙(R)-1; salt 8, (R)-1-(4-chlorophenyl)ethylamine∙(R)-1; and salt 9, (R)-1-(3-chlorophenyl)ethylamine∙(R)-1] were elucidated by X-ray crystallography. The solid-state associations and conformations of the MαNP salts were defined using the concepts of supramolecular- and planar chirality, respectively, and the crystal structures of salts 6–9 were interpreted as a three-step hierarchical assembly. The para-substituents of the (R)-1-arylethylammonium cations were found on sheet structures consisting of 2₁ columns. Thus, salts possessing smaller para-substituents, that is, salt 7 (p-F) and salt 9 (p-H), and larger para-substituents, that is, salt 6 (p-OMe) and salt 8 (p-Cl), crystallized in the space groups P2₁ and C2, respectively. Additionally, weak intermolecular interactions, that is, aromatic C–H···π, C–H···F, and C–H···O interactions, were examined in crystalline salts 6–9. Full article

(This article belongs to the Special Issue Crystal Structure Analysis of Supramolecular and Porous Solids)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Special Issue "Crystal Structure Analysis of Supramolecular and Porous Solids"

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (13 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI