There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Crystalline metal-organic frameworks (MOFs) are formed by reticular synthesis, which creates strong bonds between inorganic and organic units. Careful selection of MOF constituents can yield crystals of ultrahigh porosity and high thermal and chemical stability. These characteristics allow the interior of MOFs to be chemically altered for use in gas separation, gas storage, and catalysis, among other applications. The precision commonly exercised in their chemical modification and the ability to expand their metrics without changing the underlying topology have not been achieved with other solids. MOFs whose chemical composition and shape of building units can be multiply varied within a particular structure already exist and may lead to materials that offer a synergistic combination of properties.

The Chemistry and Applications of Metal-Organic Frameworks

J. Appl. Cryst.の発刊に際して

The long-standing challenge of designing and constructing new crystalline solid-state materials from molecular building blocks is just beginning to be addressed with success. A conceptual approach that requires the use of secondary building units to direct the assembly of ordered frameworks epitomizes this process: we call this approach reticular synthesis. This chemistry has yielded materials designed to have predetermined structures, compositions and properties. In particular, highly porous frameworks held together by strong metal-oxygen-carbon bonds and with exceptionally large surface area and capacity for gas storage have been prepared and their pore metrics systematically varied and functionalized.

/pdf/reticular-synthesis-and-the-design-of-new-materials-lazbx7tdux.pdf

Reticular synthesis and the design of new materials

Single-ligand-based electronically conductive porous coordination polymers/metal-organic frameworks (EC-PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π-conjugated EC-MOF containing copper units with mixed trigonal ligands was developed: Cu3 (HHTP)(THQ) (HHTP=2,3,6,7,10,11-hexahydrotriphenylene, THQ=tetrahydroxy-1,4-quinone). The modulated conductivity (σ≈2.53×10-5  S cm-1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2  g-1 ) of the Cu3 (HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/ange.201909096

A Dual-Ligand Porous Coordination Polymer Chemiresistor with Modulated Conductivity and Porosity.

Thin metal-organic framework (MOF) films are patterned using UV lithography and an imprinting technique. A UV lithographed SU-8 film is imprinted onto a film of MOF powder forming a 2D MOF patterned film. This straightforward method can be applied to most MOF materials, is versatile, cheap, and potentially useful for commercial applications such as lab-on-a-chip type devices.

Combining UV lithography and an imprinting technique for patterning metal-organic frameworks.

An Alkaline Earth I3O0 Porous Coordination Polymer: [Ba2TMA(NO3)(DMF)]

A Molecular Cavity for Tetrahedral and Y-Shaped Anions. Synthetic and Structural Studies of Macrocyclic Dicopper(I) and Disilver(I) Compounds of 1,6-Bis(diphenylphosphino)hexane

We report on the formation of single poly(N-vinylcarbazole) (PVCz) chains in one-dimensional channels of [La(1,3,5-benzenetrisbenzoate)]n, where the side carbazolyl groups of the confined PVCz are effectively π-stacked. This ideal conformation of PVCz chains in the coordination nanochannels contributed to a drastic increase in hole mobility, which was 5 orders of magnitude higher than that in the bulk state. It is also noteworthy that PVCz isolated from the nanchannels still had a high hole mobility.

Susumu Kitagawa

Papers

A Dual-Ligand Porous Coordination Polymer Chemiresistor with Modulated Conductivity and Porosity.

Combining UV lithography and an imprinting technique for patterning metal-organic frameworks.

An Alkaline Earth I3O0 Porous Coordination Polymer: [Ba2TMA(NO3)(DMF)]

A Molecular Cavity for Tetrahedral and Y-Shaped Anions. Synthetic and Structural Studies of Macrocyclic Dicopper(I) and Disilver(I) Compounds of 1,6-Bis(diphenylphosphino)hexane

Highly Photoconducting π-Stacked Polymer Accommodated in Coordination Nanochannels