Search results for "Structural transition"

showing 4 items of 4 documents

Exotic crystal superstructures of colloidal crystals in confinement.

2008

Colloidal model systems have been used for over three decades for investigating liquids, crystals, and glasses. Colloidal crystal superstructures have been observed in binary systems of repulsive spheres as well as oppositely charged sphere systems showing structures well known from atomic solids. In this work we study the structural transition of colloidal crystals under confinement. In addition to the known sequence of crystalline structures, crystal superstructures with dodecagonal and hexagonal symmetry are observed in one component systems. These structures have no atomic counterpart.

Condensed Matter::Quantum GasesCondensed Matter::Soft Condensed MatterCrystalColloidHexagonal symmetryMaterials scienceChemical physicsSPHERESStructural transitionColloidal crystalYablonovitePhysical review. E, Statistical, nonlinear, and soft matter physics
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Quaternary transition pathway in sol–gel encapsulated haemoglobin tracked by NIR and UV spectral relaxations

2008

→T structural transition of haemoglobin (hb), the protein responsible for oxygen (o) transport in the red blood cells of vertebrates, is the hall mark example. This transition, which regu lates o2 uptake in the lungs and o2 release in the tissues, is a switch in the quaternary structure of the protein from a low-affinity state (T) to a high-affinity state (R), two well-characterised structures. The struc tural pathway connecting the end states of this transition remains unclear, however, although recently several experimental 1 or

CrystallographyTransition (genetics)quaternary relaxationChemistryStereochemistryprotein dynamicchemistry.chemical_elementProtein quaternary structureStructural transitionQuaternaryOxygensol-gel encapsulationSol-gel
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Focus on the Essential: Extracting the Decisive Energy Barrier of a Complex Process

2019

Molecular processes at surfaces can be composed of a rather complex sequence of steps. The kinetics of even seemingly simple steps are demonstrated to depend on a multitude of factors, which prohibits applying a simple Arrhenius law. This complexity can make it challenging to experimentally determine the kinetic parameters of a single step. However, a molecular-level understanding of molecular processes such as structural transitions requires elucidating the atomistic details of the individual steps. Here, a strategy is presented to extract the energy barrier of a decisive step in a very complex structural transition by systematically addressing all factors that impact the transition kineti…

Materials scienceF300 PhysicsSingle step02 engineering and technology010402 general chemistryKinetic energy53001 natural sciencessurface scienceDissociation (chemistry)symbols.namesakeenergy barrierSurface structureStructural transitionArrhenius equationatomic force microscopyAtomic force microscopyMechanical Engineeringnanoscience021001 nanoscience & nanotechnology0104 chemical sciencesF170 Physical ChemistryArrheniusMechanics of MaterialsChemical physicssymbolsF100 Chemistry0210 nano-technologyAdvanced Materials Interfaces
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Polynitrile anions as ligands: From magnetic polymeric architectures to spin crossover materials

2010

International audience; The use of polynitrile anions as ligands (L) either alone or in combination with neutral co-ligands (L′) is a very promising and appealing strategy to get molecular architectures with different topologies and dimensionalities thanks to their ability to coordinate and bridge metal ions in many different ways. The presence of several potentially coordinating nitrile groups (or even other donor groups as –OH, –SH or –NH2), their rigidity and their electronic delocalization allow the synthesis of original magnetic high dimensional coordination polymers with transition metals ions. Furthermore, these ligands have shown coordinating and bridging capabilities in novel discr…

NitrileMetal ions in aqueous solutionMetal(II) complexesInorganic chemistry[CHIM.INOR]Chemical Sciences/Inorganic chemistry010402 general chemistry01 natural sciencesCoordination complexInorganic ChemistryDelocalized electronchemistry.chemical_compoundTransition metalSpin crossoverMagnetic propertiesMagnetic transitionMaterials Chemistry[CHIM.COOR]Chemical Sciences/Coordination chemistryPhysical and Theoretical Chemistrychemistry.chemical_classificationThermochromismThermochromism010405 organic chemistry[CHIM.ORGA]Chemical Sciences/Organic chemistryPolymer0104 chemical sciencesCoordination polymersCrystallographyPolynitrilechemistryStructural transitionNitrile ligandCyano ligand
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