The First “Organic Zeolite” with Isomerizing Building Blocks:  Single-Crystal-to-Single-Crystal Desolvation and Structure of the Empty Matrix

The 1D {[CuII(cyclam)]3[WV(CN)8]2.5H2O}n (1·5H2O) (cyclam = 1,4,8,11-tetraazacyclotetradecane) coordination polymer of ladder topology can be obtained in water-alcohol solution from [Cu(cyclam)]2+ and [W(CN)8]3− building blocks. Upon dehydration, 1·5H2O undergoes a single-crystal-to-single-crystal structural transformation to the anhydrous {[CuII(cyclam)]3[WV(CN)8]2}n (1) form, which retains the same topology, but is characterized by shorter Cu-W distances and significantly more bent CN-bridges. The deformation of the coordination skeleton is reflected in magnetic properties: the predominant intra-chain interactions change from ferromagnetic in 1·5H2O to antiferromagnetic in 1. The reaction between the same building blocks in water solution under slow diffusion conditions leads to the formation of a 0D {[CuII(cyclam)(H2O)]2[CuII(cyclam)][WV(CN)8]2}.3H2O pentanuclear assembly (2·3H2O).

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(S)-Pramipexole and Its Enantiomer, Dexpramipexole: A New Chemoenzymatic Synthesis and Crystallographic Investigation of Key Enantiomeric Intermediates

Catalysts ◽

10.3390/catal10080941 ◽

2020 ◽

Vol 10 (8) ◽

pp. 941

Author(s):

Samuele Ciceri ◽

Patrizia Ferraboschi ◽

Paride Grisenti ◽

Shahrzad Reza Elahi ◽

Carlo Castellano ◽

...

Keyword(s):

Single Crystal ◽

Enantiomeric Excess ◽

Three Dimensional ◽

Building Blocks ◽

Chemoenzymatic Synthesis ◽

Racemic Mixture ◽

Candida Antarctica Lipase ◽

Crystallographic Investigation ◽

Reaction Conditions ◽

X Ray

A new chemoenzymatic method has been developed for the synthesis of (S)- and (R)-N-(6-hydroxy-4,5,6,7-tetrahydrobenzo[d]thiazol-2-yl) acetamide, two key synthons for the preparation of (S)-pramipexole, an anti-Parkinson drug, and its enantiomer dexpramipexole, which is currently under investigation for the treatment of eosinophil-associated disorders. These two building blocks have been obtained in good yields and high enantiomeric excess (30% and >98% ee for the R-enantiomer, and 31% and >99% ee for the S- one) through a careful optimization of the reaction conditions, starting from the corresponding racemic mixture and using two consecutive irreversible transesterifications, catalyzed by Candida antarctica lipase type A. Single crystal X-ray analysis has been carried out to unambiguously define the stereochemistry of the two enantiomers, and to explore in depth their three-dimensional features.

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High-performance, semiconducting membrane composed of ultrathin, single-crystal organic semiconductors

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1909932116 ◽

2019 ◽

Vol 117 (1) ◽

pp. 80-85 ◽

Cited By ~ 5

Author(s):

Tatsuyuki Makita ◽

Shohei Kumagai ◽

Akihito Kumamoto ◽

Masato Mitani ◽

Junto Tsurumi ◽

...

Keyword(s):

Single Crystal ◽

Organic Semiconductors ◽

High Performance ◽

Printed Electronics ◽

Electronic Device ◽

Molecular Layer ◽

High Mobility ◽

Building Blocks ◽

Solution Processed ◽

Transfer Method

Thin film transistors (TFTs) are indispensable building blocks in any electronic device and play vital roles in switching, processing, and transmitting electronic information. TFT fabrication processes inherently require the sequential deposition of metal, semiconductor, and dielectric layers and so on, which makes it difficult to achieve reliable production of highly integrated devices. The integration issues are more apparent in organic TFTs (OTFTs), particularly for solution-processed organic semiconductors due to limits on which underlayers are compatible with the printing technologies. We demonstrate a ground-breaking methodology to integrate an active, semiconducting layer of OTFTs. In this method, a solution-processed, semiconducting membrane composed of few-molecular-layer–thick single-crystal organic semiconductors is exfoliated by water as a self-standing ultrathin membrane on the water surface and then transferred directly to any given underlayer. The ultrathin, semiconducting membrane preserves its original single crystallinity, resulting in excellent electronic properties with a high mobility up to 12cm2⋅V−1⋅s−1. The ability to achieve transfer of wafer-scale single crystals with almost no deterioration of electrical properties means the present method is scalable. The demonstrations in this study show that the present transfer method can revolutionize printed electronics and constitute a key step forward in TFT fabrication processes.

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Radially oriented mesoporous TiO2 microspheres with single-crystal–like anatase walls for high-efficiency optoelectronic devices

Science Advances ◽

10.1126/sciadv.1500166 ◽

2015 ◽

Vol 1 (4) ◽

pp. e1500166 ◽

Cited By ~ 89

Author(s):

Yong Liu ◽

Renchao Che ◽

Gang Chen ◽

Jianwei Fan ◽

Zhenkun Sun ◽

...

Keyword(s):

Single Crystal ◽

Mesoporous Materials ◽

High Performance ◽

High Efficiency ◽

Dye Sensitized Solar Cells ◽

Building Blocks ◽

Accessible Surface Area ◽

Photoelectric Conversion Efficiency ◽

Photoelectric Conversion ◽

Assembly Method

Highly crystalline mesoporous materials with oriented configurations are in demand for high-performance energy conversion devices. We report a simple evaporation-driven oriented assembly method to synthesize three-dimensional open mesoporous TiO2 microspheres with a diameter of ~800 nm, well-controlled radially oriented hexagonal mesochannels, and crystalline anatase walls. The mesoporous TiO2 spheres have a large accessible surface area (112 m2/g), a large pore volume (0.164 cm3/g), and highly single-crystal–like anatase walls with dominant (101) exposed facets, making them ideal for conducting mesoscopic photoanode films. Dye-sensitized solar cells (DSSCs) based on the mesoporous TiO2 microspheres and commercial dye N719 have a photoelectric conversion efficiency of up to 12.1%. This evaporation-driven approach can create opportunities for tailoring the orientation of inorganic building blocks in the assembly of various mesoporous materials.

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Assembling the Building Blocks for Diamond Electronics

MRS Proceedings ◽

10.1557/proc-0956-j01-02 ◽

2006 ◽

Vol 956 ◽

Author(s):

William Joseph Yost

Keyword(s):

Single Crystal ◽

Large Scale ◽

Building Blocks ◽

Thin Layers ◽

Bulk Single Crystal ◽

High Quality ◽

Ambient Temperatures ◽

Single Crystal Diamond ◽

Key Issues ◽

Grade Material

ABSTRACTThe desire to exploit the extreme properties which differentiate diamond from other, more mature wide bandgap technologies has recently been given further impetus by the development of high quality single crystal CVD diamond material [1].To realise the significant potential of diamond devices over existing device technology depends on completing a number of key objectives, in particular providing:(a). access in volume to high quality, ultra-high purity, single crystal material,(b). the capability to provide carriers by doping the material in a controlled manner,(c). the ability to process thin layers and structures.Providing access to bulk single crystal diamond (albeit not electronic grade material) has already been largely achieved and plates are commercially available for cutting applications [2]. Routes to providing suitable charge carriers are being widely investigated. Although intrinsic diamond can have exceptional electronic properties [1], in reports of both p-type and n-type diamond [3,4] the dopants are very deep (0.37 eV and 0.6 eV for boron and phosphorous respectively), which limits the realisation of conventional electronic devices operating at ambient temperatures.A series of novel devices undergone preliminary experimental evaluation. Devices made up of boron and intrinsic layers, where the boron concentration exceeds the limit of metallic conduction (>1×1020 cm−3), offer carrier diffusion at room temperature from the highly doped regions with low mobility, into adjacent regions of intrinsic material with high carrier mobility [5]. To provide the required device performance, the interface between the doped and intrinsic layers needs to be defect free and to change doping levels by several orders of magnitude in a few atomic layers.Although progress over the last few years has been rapid, there remain substantial technical challenges ahead for the realisation of large scale diamond active electronics. This paper will identify and review progress against these key issues.

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Synthesis and Structure of a Metal-Organic Solid Having the Cadmium(II) Sulfate Net

MRS Proceedings ◽

10.1557/proc-453-127 ◽

1996 ◽

Vol 453 ◽

Cited By ~ 5

Author(s):

O. M. Yaghi ◽

Hailian Li ◽

M. O'Keeffe

Keyword(s):

Single Crystal ◽

Building Blocks ◽

Relative Orientation ◽

X Ray ◽

Open Framework ◽

Elemental Microanalysis ◽

Organic Solid ◽

Metal Organic

AbstractReaction of silver(I) nitrate and hexamethylenetetramine (HMTA) gives crystals of Ag2(HMTA)(NO3)2, which was formulated by elemental microanalysis and a single crystal x-ray study. Its Ag2(HMTA) open-framework is the first example of a decorated CdSO4net. The relative orientation of the tetrahedral HMTA building blocks in this structure point to numerous opportunities toward constructing novel chiral and polar porous frameworks.

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Nanocrystalline Oxides: CdS nanowires synthesized by solvothermal method

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314085854 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1414-C1414

Author(s):

Nomery Hadia ◽

Santiago Garcia-Granda ◽

Jose Garcia

Keyword(s):

Metal Oxide ◽

Single Crystal ◽

Research Programme ◽

Building Blocks ◽

Mediterranean Area ◽

Near Band Edge ◽

Band Edge Emission ◽

One Dimensional ◽

Wide Range ◽

Cds Nanowires

Recent advances in the field of nanotechnology produced an assortment of one-dimensional (1D) structures, such as nanowires and nanorods. These fascinating materials are the potential building blocks for a wide range of nanoscale electronics, optoelectronics, magnetoelectronics, or sensing devices [1]. Parallel to the success with group IV and groups III–V compounds semiconductor nanostructures, semiconducting metal oxide materials with wide band gaps are attracting attention [2-3]. The main aim of this communication is to report our results on the application of several new techniques, particularly the use of hydrothermal synthesis, to fabricate single crystal one-dimensional nanostructured materials, study their growth processes, understand the growth mechanisms and investigate their physical properties. A wide range of remarkable features are then presented, to cover a number of metal oxides, such as ZnO, Sb2O3, CdS, MgO, α-Fe2O3, or TiO2, describing their structures, optical, magnetic, mechanical and chemical sensing properties. These studies constitute the basis for developing versatile applications based on metal oxide 1D systems as well as highlighting the current progress in device development. To exemplify, the as-prepared CdS nanowires have average 28 nm in diameter and length up to several micrometres. The direct band gap of the CdS nanowires is 2.56 eV calculated by the UV-vis absorption spectra. The PL spectrum has two distinct emission bands at 502 nm and 695 nm, which are associated with the near-band-edge emission and defect emission, respectively. These synthesized single-crystal CdS nanowires have a high potential in the optoelectronic applications of nanolasers, solar cells, lighting-emitting diodes or photodetectors. Acknowledgments: Erasmus Mundus MEDASTAR (Mediterranean Area for Science, Technology and Research) Programme, 2011–4051/002–001-EMA2, Spanish MINECO (MAT2010-15094, Factoría de Cristalización – Consolider Ingenio 2010) and ERDF.

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Polyhalides as scaffolds for supramolecular, ion-conducting crown ether stacks

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314093656 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C634-C634

Author(s):

Katharina Fromm ◽

Aurélien Crochet ◽

Cyrille Dagri ◽

Yvens Chérémond

Keyword(s):

Solid State ◽

Single Crystal ◽

Crown Ethers ◽

Halogen Bonding ◽

Building Blocks ◽

Channel Formation ◽

One Dimensional ◽

Naoh Solution ◽

Ion Conducting

"Crown ethers, such as dibenzo-18-crown-6 (DB18C6) are in principle perfect building blocks to be stacked on top of each other for one-dimensional (1D) channel formation. However, in the more than 1000 publications on crown ethers in the solid state, only one case was of channel formation described, but not as main focus of research.[1] We now present a way to systematically induce the stacking of DB18C6 with the help of polyhalides, which play the roles of scaffolds via halogen bonding.[2] These compounds can be considered as ""supramolecular straws"". Using for example potassium as couter ion for triiodide for example, we obtained a solid which contains three differently filled, parallel channels in the solid state, which are arranged between the polyhalide anions. Exchanging potassium with sodium by immersion of a single crystal into NaOH solution leads to a single-crystal-to-single-crystal transformation into a compound with two channel types. This transition from a system crystallizing initially in the P2-space group to yield a compound in Pccn is only possible under these very special conditions. We will further present how the ion transport through these channels can be quantified and which process is involved in ion exchange. The role of the polyhalide anions, which cannot be replaced by other linear anions, will be emphasized as well. "

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Molecular assembly of 1,3,5-tris(cyanomethyl) and 1,4-bis(cyanomethyl)arenes with silver triflate

Pure and Applied Chemistry ◽

10.1351/pac200678040855 ◽

2006 ◽

Vol 78 (4) ◽

pp. 855-871 ◽

Cited By ~ 6

Author(s):

Kathleen V. Kilway ◽

Shiping Deng ◽

Sean Bowser ◽

Joseph Mudd ◽

Laronda Washington ◽

...

Keyword(s):

Single Crystal ◽

Layered Structure ◽

Building Blocks ◽

Molecular Assembly ◽

Porous Channel ◽

X Ray Diffraction ◽

X Ray ◽

Silver Triflate

Dicyano- and tricyano-substituted aromatic angular building blocks were systematically complexed with silver triflate, and their structures were determined by means of single-crystal X-ray diffraction. The molecular assembly of 1,3,5-tris(cyanomethyl)-2,4,6-triethylbenzene with silver triflate from benzene resulted in a layered structure with distorted square pyramidal silver sites. The structure resulting from the complexation of 1,3,5-tris(cyanomethyl)-2,4,6-trimethylbenzene with silver triflate is dependent on the solvent of crystallization. From benzene or toluene, reaction of 1,3,5-tris(cyanomethyl)-2,4,6-trimethylbenzene with silver triflate yielded a porous, channel-containing, solvated structure, but from acetone the resulting material was a network solid containing no solvent. Complexation of 1,4-bis(cyanomethyl)-2,3,5,6-tetraethylbenzene and 1,4-bis(cyanomethyl)-2,3,5,6-tetramethylbenzene with silver triflate resulted in network solids where the triflate anions were strongly coordinated to the silver.

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