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

: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Supramolecular materials, dynamic materials by nature, are defined as materials whose components are bridged via reversible connections and undergo spontaneous and continuous assembly/disassembly processes under specific conditions. On account of the dynamic and reversible nature of noncovalent interactions, supramolecular polymers have the ability to adapt to their environment and possess a wide range of intriguing properties, such as degradability, shape-memory, and self-healing, making them unique candidates for supramolecular materials. In this critical review, we address recent developments in supramolecular polymeric materials, which can respond to appropriate external stimuli at the fundamental level due to the existence of noncovalent interactions of the building blocks.

Stimuli-responsive supramolecular polymeric materials.

Perylene Bisimide Dye Assemblies as Archetype Functional Supramolecular Materials

It is a challenge to synthesize materials that possess the properties of biological muscles-strong, elastic and capable of self-healing. Herein we report a network of poly(dimethylsiloxane) polymer chains crosslinked by coordination complexes that combines high stretchability, high dielectric strength, autonomous self-healing and mechanical actuation. The healing process can take place at a temperature as low as -20 °C and is not significantly affected by surface ageing and moisture. The crosslinking complexes used consist of 2,6-pyridinedicarboxamide ligands that coordinate to Fe(III) centres through three different interactions: a strong pyridyl-iron one, and two weaker carboxamido-iron ones through both the nitrogen and oxygen atoms of the carboxamide groups. As a result, the iron-ligand bonds can readily break and re-form while the iron centres still remain attached to the ligands through the stronger interaction with the pyridyl ring, which enables reversible unfolding and refolding of the chains. We hypothesize that this behaviour supports the high stretchability and self-healing capability of the material.

A highly stretchable autonomous self-healing elastomer

This critical review summarizes the research progress made in the field of π-conjugated terpyridines within the last decade. Supramolecular materials based on metal ion complexes of 2,2′:6′,2″-terpyridine derivatives have found manifold potential applications—from opto-electronic devices to life science. In this contribution, synthetic strategies towards π-conjugated terpyridines and their incorporation into advanced supramolecular architectures are evaluated. Applications as photoactive species in, e.g., photovoltaic devices, polymer light-emitting diodes (PLEDSs) and nanotechnology are discussed comprehensively (523 references).

Advances in the field of π-conjugated 2,2':6',2"-terpyridines.

The incorporation of metal centers into the backbone of polymers has led to the development of a broad range of organometallic and coordination compounds featuring properties that are relevant for potential applications in diverse areas of research, ranging from energy storage/conversion to bioactive or self-healing materials. In this review, the basic concepts and synthetic strategies leading to these types of materials as well as the scope of available characterization techniques will be summarized and discussed.

Synthesis and characterization of metallo-supramolecular polymers

Pyridine-based ligands, such as 2,2'-bipyridine and 1,10-phenanthroline, have gained much interest in the fields of supramolecular chemistry as well as materials science. The appealing optoelectronic properties of their complexes with heavy d(6) transition metal ions, such as Ru(ii), Os(II), Re(I) and Ir(III), primarily based on the metal-to-ligand charge-transfer (MLCT) nature featuring access to charge-separated states, have provided the starting point for many studies in the field of dye-sensitized solar cells (DSSCs), organic light emitting diodes (OLEDs), artificial photosynthesis and photogenerated electron as well as energy transfer processes. This critical review provides a comprehensive survey over central advances in the field of soluble metal-containing macromolecules in the last few decades. The synthesis and properties of functionalized 2,2'-bipyridyine- and 1,10-phenanthroline-based d(6) metal complexes, in particular, their introduction into different prevailing polymeric structures are highlighted. In the most part of the review metal complexes which have been attached as pendant groups on the polymer side chain are covered. Selected applications of the herein discussed metal-containing macromolecules are addressed, particularly, with respect to photogenerated electron/energy transfer processes. In order to enable a deeper understanding of the properties of the ligands and metal complexes, the fundamentals of selected photophysical processes will be discussed (223 references).

Photogenerated avenues in macromolecules containing Re(I), Ru(II), Os(II), and Ir(III) metal complexes of pyridine-based ligands.

Phenyl-1H-[1,2,3]triazoles as New Cyclometalating Ligands for Iridium(III) Complexes

The coordination compounds of the tridentate oligopyridine ligand 2,2′:6′,2′′-terpyridine (tpy) are utilized in very different fields of research, such as materials science (e.g. photovoltaics), biomedicinal chemistry (e.g. DNA intercalation), and organometallic catalysis. Applications in the latter area have arisen from initial reports on electro- or photochemical processes and, today, a broad range of reactions—from artificial photosynthesis (water splitting) to biochemical and organic transformations as well as polymerization reactions—have been catalyzed by terpyridines and their transition metal complexes. In this review, the scope and the limitations of these applications, which emerged particularly in organic and macromolecular chemistry, will be evaluated.

Andreas Winter

Papers

Advances in the field of π-conjugated 2,2':6',2"-terpyridines.

Synthesis and characterization of metallo-supramolecular polymers

Photogenerated avenues in macromolecules containing Re(I), Ru(II), Os(II), and Ir(III) metal complexes of pyridine-based ligands.

Phenyl-1H-[1,2,3]triazoles as New Cyclometalating Ligands for Iridium(III) Complexes

Catalytic Applications of Terpyridines and their Transition Metal Complexes