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Structures Clustering

In the same paper (Yamamoto 1996) an authoritative description is given of several interrelated topics such as super-space group determination, structure determination, indexing of diffraction patterns of quasicrystals, polygonal tiling, icosahedral tiling, structure factor calculation, description of quasicrystal structures, cluster models of quasicrystals. [Pg.203]

Only one class modeling method is conmonly applied to analytical data and this is the SIMCA method ( ) of pattern recognition. In this method the class structure (cluster) is approximated by a point, line, plane, or hyperplane. Distances around these geometric functions can be used to define volumes where the classes are located in variable space, and these volumes are the basis for the classification of unknowns. This method allows the development of information beyond class assignment ( ). [Pg.246]

Average oxidation number of the meted Close-packed structures Cluster strucures... [Pg.667]

A group of nanomaterials, as the only criterion of membership becomes particle size, is very diversified. Particular members of the group differ from each other by molecular geometry (i.e., nanotubes, fullerenes, crystal structures, clusters, etc.) and physicochemical characteristics (i.e., organic, inorganic, semiconductors, isolators, metals, nonmetals, etc.). Thus, it may and should be assumed that they also differ by the mechanism of action and - in consequence - defining one common applicability domain and QSAR model for all of them is impossible. [Pg.208]

Madabushi S, Yao H, Marsh M, Kristensen DM, Philippi A, Sowa ME, Lichtaige O. Structural clusters of evolutionaiy trace residues are statistically significant and common in proteins. J Mol Biol 2002 316 139-154. [Pg.29]

Figure 6.11 Structural cluster models for amylopectin as proposed by (a) French 67 (b) Robin et al. 285 and (c) Manners and Matheson.290 1 and 2 in the model represent crystalline and amorphous regions, respectively. Figure 6.11 Structural cluster models for amylopectin as proposed by (a) French 67 (b) Robin et al. 285 and (c) Manners and Matheson.290 1 and 2 in the model represent crystalline and amorphous regions, respectively.
Molecule C2o is the smallest one from all the fullerenes [9] and has the form of dodecahedra (point symmetry group Yh). We consider here only polymerized structures (clusters) which are formed by the pairs of bridge like bonds directed along molecules second order axes. The clusters formation is accompanied by the distortion of the geometry of molecules that leads as sequence to decreasing the symmetry both molecule and cluster (for example the symmetry group of cluster (C2o)s is only D2h). [Pg.714]

A set of building blocks (a BBL) may be clustered, i.e. the S-space contains dense regions of structures, clusters, with empty space in between. If things are done properly each cluster will contain similar compounds. In this case, a separate SMD made for each cluster will provide an adequate representation of the whole S-space [32], If there are compounds between the clusters, a separate designed selection of these should be made to complement the selection ofBBs. [Pg.207]

The main reason is that all the systems are relatively complex and, while spectroscopic techniques may give part of the answer as to the nature and stereochemistry of the compound, a full crystallographic study will in a vast majority of cases give a definitive answer. In the reviews on alkyne-substituted clusters and related compounds, a large proportion of the discussion of the chemistry has been based on solid-state structural data, and this review is no exception. The variety of structural cluster types incorporating alkyne ligands will be presented in Section IV. [Pg.191]

Second, the theory that the screening of only one representative per structural cluster is sufficient to determine the activity of the cluster assumes that the screening procedure is error free. [Pg.216]

This approach has been particularly developed for application to macropolyhe-dral structures, clusters involving linked polyhedra, and many examples have been described in detail. ... [Pg.586]

However, the run of the ZFC magnetization curve does not correspond to the results of TEM, EPR and IR spectroscopy results concerning particle size of y-Fe20j and the absence of its interaction with Si02 matrix. Thus, a wide maximum T ax at 145 K is typical of greater particles [1-2,4] as compared to the studied materials. A considerable distinction between T ax and Tsep (250 K) is the evidence of a wide particle size distribution. The mentioned contradictions between the particle size and magnetic behavior of the samples can be resolved considering that and T ep parameters depend not only on a particle size, but on a number of other features of materials like surface states, defectiveness of structure, cluster interaction [5]. [Pg.368]

Klein, D.J., Schmalz, T.G. and Bytautas, L. (1999). Chemical Sub-Structural Cluster Expansions for Molecular Properties. SAR <6 QSAR Environ.Res., 10,131-156. [Pg.601]

Figure 21. Radial distribution functions calculated using a Fourier transform of scattering patterns produced with a Debye equation. Top Cuboctahedron (cluster with both octahedral 111 and cnbe 100 faces) and icosahedron (multiply twinned hep structure) clusters of the same size. Center Cuboctahedra of different sizes. Bottom Experimental and simulated cluster RDF of a Pt colloid. The fit is a 90 10 mixture of 55 and 147 cuboctahedral clusters, respectively. After Casanove et al. (1997). Figure 21. Radial distribution functions calculated using a Fourier transform of scattering patterns produced with a Debye equation. Top Cuboctahedron (cluster with both octahedral 111 and cnbe 100 faces) and icosahedron (multiply twinned hep structure) clusters of the same size. Center Cuboctahedra of different sizes. Bottom Experimental and simulated cluster RDF of a Pt colloid. The fit is a 90 10 mixture of 55 and 147 cuboctahedral clusters, respectively. After Casanove et al. (1997).
Knowledge of one implies knowledge of the other. As sure as Bragg scattering measures the structure of a crystal in q space, so too the structure factor of a cluster measured optically represents the structure cluster in q space. [Pg.638]

In order to understand the reactivity of ceria surfaces and the interaction of it with metal particles or adsorbates, it is of fundamental interest to know its surface structure and the extent or type of defects present. Even though the film may be an oriented single crystal, there is still the question of whether the surface is terminated in oxygen anions, Ce cations, a mixture or in defects associated with the termination. Charge neutrality, interfacial relaxation and dielectric discontinuities may modify the properties of an oxide surface. Also the ability of the surface to adsorb or give up oxygen, as well as the structure, clustering and reactivity of defects may be expected to depend upon the surface orientation and structure. [Pg.318]


See other pages where Structures Clustering is mentioned: [Pg.61]    [Pg.263]    [Pg.171]    [Pg.165]    [Pg.157]    [Pg.379]    [Pg.315]    [Pg.70]    [Pg.137]    [Pg.674]    [Pg.118]    [Pg.237]    [Pg.169]    [Pg.24]    [Pg.343]    [Pg.721]    [Pg.238]    [Pg.177]    [Pg.15]    [Pg.166]    [Pg.270]    [Pg.2309]    [Pg.2675]    [Pg.206]    [Pg.674]    [Pg.30]    [Pg.661]    [Pg.570]    [Pg.331]   
See also in sourсe #XX -- [ Pg.6 , Pg.145 , Pg.146 ]




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Aluminum cluster structure

Argon, cluster structure

Backbone structure cluster structures

Band structure cluster complexes

Borane cluster compounds structures

Carbidocarbonyl clusters structures

Carbon clusters amorphous structures

Carbon clusters electronic structure calculations

Carbon clusters geometrical structure

Carbon dioxide clusters structure

Carbonyl clusters structural parameters

Cationic clusters lowest-energy structure

Central structural unit polynuclear clusters

Closed-cluster composition and structure

Cluster Analysis Recognition of Inherent Data Structures

Cluster and cage structure

Cluster compounds state intermetallic structures

Cluster fractal structure

Cluster fractal structure chaotic fractals

Cluster fractal structure conductivity

Cluster fractal structure lattice structural models

Cluster fractal structure percolation threshold values

Cluster model electronic structure

Cluster models structural transitions

Cluster structural features

Cluster structure elements

Cluster structure transformation

Cluster structure, zero temperature

Cluster structures

Cluster structures

Cluster structures bare metal anions

Cluster structures bare metal cations

Cluster structures multi-element clusters

Cluster structures production

Cluster structures, classification

Clustering of Structures

Clustering of chemical structures

Clustering structural data

Clusters and crystal structures

Clusters central structural units

Clusters crystal structure

Clusters geometrical structure

Clusters metallic, shell structure

Clusters structural descriptors

Coordination complexes cluster structures

Coupled-cluster electronic structure

Crystal structure calculation cluster method

Crystal structure cluster complexes

Crystal structure prediction clustering

Cubane-type clusters structural parameters

Effects of Electron Correlations and Structure on Cluster Magnetism

Electronic Structure of Metal and Mixed Nonstoichiometric Clusters

Electronic Structure of Naked, Ligated and Supported Transition Metal Clusters from First Principles Density Functional Calculations

Electronic structure cluster complexes

Electronic structure of clusters

Electronic structure of supported clusters

Electronic structure of transition metal clusters

Electronic structure silicon clusters

Electronic structures clusters

Flickering cluster model structure

Fluorite structure defect clusters/cluster models

Fullerene cluster structure

Geometric cluster structure

Gold cluster complexes structure

Gold clusters structures

Gradient-based Methods for Determination of Cluster Structures at Zero Temperature

Group 5 metal halide clusters electronic structure

Group 5 metal halide clusters molecular structure

Heteronuclear clusters structures

Hexanuclear clusters electronic structures

Hydride-transition metal clusters, structures

Icosahedral clusters structure

Induction cluster polarization, structure

Iron clusters structure

Iron, alkyne-substituted clusters structures

Iron-molybdenum-sulfur clusters crystal structure

Iron-molybdenum-sulfur clusters structure

Iron-platinum cluster structure

Iron-sulfur clusters structure

Isoelectronic cluster structure

Krypton, cluster structure

Magnesium clusters structure

Metal cluster superconductors structure

Metal clusters closed electronic structure

Metal clusters structure

Metal clusters, transition structure variation

Metal oxide clusters electronic structures

Methane clusters structure

Mo6S8 cluster, structure

Molecular clusters structure

Molecular structures phase cluster formation

Molybdenum cluster compounds electronic structure

Molybdenum cluster compounds molecular structure

Multiplet structures model clusters

Nafion cluster structure

Nanoscale chemical structure clusters

Neon, cluster structure

Niobium halide clusters electronic structure

Nitrogen cluster structure

Nitrosyl clusters structures

Optimized Structures for the and Clusters

Osmium carbonyl cluster anions, structures

Osmium carbonyl clusters structure

P clusters, structure

Palladium small clusters, electronic structure

Percolation theory cluster structure

Phosphides with clusters structures

Photosystem II manganese cluster of, structure

Platinum carbonyl cluster anions, structure

Polynuclear clusters, structure

Protein Structure Similarity Clustering

Protein structure similarity clustering PSSC)

Putative structure cluster

Reactions Leading to Structural Changes in Clusters

Rhenium catalysts cluster structures

Rhodium carbonyl cluster anion, structure

Rules for Cluster Structure-Electron Counting Correlations

Ruthenium-copper clusters structure

Sodium clusters electronic shell structures

Sodium clusters structure optimizations

Sodium clusters structures

Structural Characteristics of Molecular Metal Clusters

Structural Dynamics of the Active Re10 Cluster

Structural and Bonding Patterns Cluster Chemistry

Structural and Reactivity Aspects of Hetero-Pt Clusters

Structural and Temperature Behavior of Metallic Clusters

Structural cluster model

Structural transition mechanisms, potential clusters

Structure Supercritical” cluster

Structure and Bonding in Heteronuclear Gold Cluster Compounds

Structure and Bonding in Transition-Metal Clusters

Structure and Properties of Ligated Clusters

Structure and Properties of Naked Clusters

Structure and Reactivity of Clusters on Surfaces

Structure cluster complexes

Structure of Au clusters

Structure of Smaller Carbon Clusters

Structure of carbonyl clusters

Structure of clusters

Structure of clusters with

Structure with substituted carbonyl clusters

Structures and Bonding of Coinage Metal NPFM Clusters

Structures of homoatomic nine-atom clusters

Structures tetrahedral clusters

Structures with finite clusters of tetrahedra and octahedra

Sulfur dioxide clusters structure

The Roles of Cluster Structure in Copper-mediated Reactions

The Structure of Hydride Clusters

Topological structure cluster relationships

Topological structure clustering

Transition metal clusters structural data

Transition metal clusters, boron atoms structure

Transition-metal clusters structure

Trigonal pyramidal structures, atomic clusters

Trinuclear iron-sulfur clusters structures

Ultrafast dynamics cluster structures

Vanadium nitrogenase cluster structure

Water cluster structure

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