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

Die Chemie der Koordinationspolymere hat sich in den vergangenen Jahren rasant entwickelt. Strukturen aus einer Vielzahl molekularer Bausteine mit unterschiedlichen Wechselwirkungen sind mittlerweile zuganglich. Die nachste Stufe ist die chemische und physikalische Funktionalisierung dieser Architekturen durch Einstellung ihrer Porositaten. Dieser Aufsatz konzentriert sich auf drei Aspekte von Koordinationspolymeren: 1) Anwendung von Kristall-Engineering zum Aufbau poroser Geruste aus Konnektoren und Linkern (“Nanospace-Engineering”), 2) Charakterisierung und Katalogisierung poros-struktureller Funktionalitat fur Anwendungen in Speicherungs-, Austausch-, Trennprozessen etc. und 3) poros-strukturelle Funktionalitat auf der Basis dynamischer Kristallumwandlungen durch Gastmolekule oder physikalische Reize. Ziel ist es, den aktuellen Stand der Forschung zur Chemie und Physik von und in den Mikroporen poroser Koordinationspolymere vorzustellen.

Funktionale poröse Koordinationspolymere

Three‐Dimensional Framework with Channeling Cavities for Small Molecules: {[M2(4, 4′‐bpy)3(NO3)4]·xH2O}n (M Co, Ni, Zn)

Porous Coordination‐Polymer Crystals with Gated Channels Specific for Supercritical Gases

A New, Methane Adsorbent, Porous Coordination Polymer [{CuSiF6(4,4′-bipyridine)2}n]

A set of terms, definitions, and recommendations is provided for use in the classi- fication of coordination polymers, networks, and metal-organic frameworks (MOFs). A hier- archical terminology is recommended in which the most general term is coordination poly- mer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains poten- tial voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended.

/pdf/terminology-of-metal-organic-frameworks-and-coordination-ha0o04iyzo.pdf

Susumu Kitagawa

Papers

Funktionale poröse Koordinationspolymere

Three‐Dimensional Framework with Channeling Cavities for Small Molecules: {[M2(4, 4′‐bpy)3(NO3)4]·xH2O}n (M Co, Ni, Zn)

Porous Coordination‐Polymer Crystals with Gated Channels Specific for Supercritical Gases

A New, Methane Adsorbent, Porous Coordination Polymer [{CuSiF6(4,4′-bipyridine)2}n]

Terminology of metal–organic frameworks and coordination polymers (IUPAC Recommendations 2013)