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Electron clusters

Just as the Mo6Xg units in the Chevrel phases tolerate a certain lack of electrons (e.g. 20 instead of 24 skeleton electrons), clusters with M6X12 units which have fewer than 16 skeleton electrons are also possible. For example, in Zr6I12 there are only 12 skeleton electrons, and Sc7Cl12 = Sc3+[Sc6C112]3- has only nine. [Pg.144]

The doubly bonded complexes V Cli y-OR)2(0R)2(ROH)2 are different from the fully substituted tungsten(IV) alkoxides Wi+(0R)ie (JL,9), in that the latter 8-electron cluster exhibits a considerable degree of delocalized W-W bonding, the shortest W-W distance (2.65A) being much longer than the W=W bond (2.48A) in I Cli -(y-OR) 2(OR)2(ROH)2 (4). [Pg.261]

X-ray powder patterns showed that the product of this reaction is indeed isomorphous with Zn2Mo308 and hence is the desired 7-electron cluster derivative. Unfortunately single crystals for a complete structure determination have not been obtained. Subsequent work (17) however showed that additional cations could... [Pg.265]

Multicenter bonding is the key to understanding carboranes. Classical multicenter n bonding gives rise to electron-precise structures characteristic of Hiickel aromatics, which are planar and have 4n + 2 n electrons. Clusters are defined here as ensembles of atoms connected by non-classical multicenter bonding , i.e., all... [Pg.267]

Series Parent Formula Skeletal Electrons Cluster Geometry (deltahedron = closed triangulated polyhedron)... [Pg.126]

With respect to CO adsorption on neutral Aun clusters, our preliminary results show differences with previous calculations using cluster geometries extracted from the fee gold crystal. The adsorption energy of CO is minimum for the planar magic cluster Aue and shows maxima for the odd electron clusters Au5 and Au7, both with the CO absorbed on a bridge position, but the even-odd effect is not obtained for sizes larger than n=7. [Pg.430]

The reaction of the preformed 16-electron clusters [ (Ph3P)Au 8M](N03)2 (M = Pt, Pd) with metallic Hg resulted in isolation of the isomorphous 20-electron clusters [ (Ph3P) Au 8M (Hg)2] (N03)2 in which two mercury atoms cap in a (i4-fashion the gold atoms of two opposite square faces in an M-centered square-antiprism [Au-Hg 2.915... [Pg.191]

The preceding three reduced molybdenum clusters indicate that rhomboidal cluster units are common among this kind of oxide, and the Mo-Mo distances in the cluster units are dependent on CVE assignable to the Mo4 units. MO calculations on Mo4 molecular cluster compounds containing 10 CVE and 8 CVE have shown that the 8-electron clusters distort from a second-order Jahn-Teller effect (116). Such a distortion has been observed in the 8-electron W4(OEt)16 (117). [Pg.81]

The bonding capabilities of transition metal clusters (no nonmetals in the framework), based on molecular orbital calculations, has been nicely summarized by Lauher14 (Table 16.3). Within this table we see three structures (tetrahedron, butterfly, and square plane) for tetranuclear metal clusters. The tetrahedron is a 60-electron cluster, while the butterfly and square plane clusters have 62 and 64 electrons. respectively. When we go from a tetrahedron to a butterfly, one of the edges of the tetrahedron is lengthened corresponding to bond breaking. [Pg.938]

High-yield syntheses of Os3Pt clusters are available using this rationale. Thus treatment of Os3(/i-H)2(CO)10, which contains a formal Os=Os double bond, with Pt(C2H4)2(PR3) affords the tetrahedral 58-electron cluster Os3Pt(/i-H)2(CO)10(PR3) (1) (40,40a), whereas with the bis-phosphine reagent... [Pg.304]

Whereas in ligand bridged dinuclear complexes, removal or addition of two electrons makes or breaks one metal-metal bond (15) this does not seem to be the case for clusters, presumably because of their delocalized bonding. At least for one case, however, two-electron reduction can induce a significant change in cluster shape (18,42) the 84-electron cluster Os6(CO),g with framework 1 is easily reduced to the 86-electron anion Os6(CO) g with framework 2, in accordance with skeletal electron counting rules. [Pg.173]


See other pages where Electron clusters is mentioned: [Pg.66]    [Pg.1031]    [Pg.1142]    [Pg.84]    [Pg.85]    [Pg.90]    [Pg.1088]    [Pg.1089]    [Pg.237]    [Pg.378]    [Pg.241]    [Pg.353]    [Pg.397]    [Pg.23]    [Pg.371]    [Pg.113]    [Pg.21]    [Pg.7]    [Pg.8]    [Pg.190]    [Pg.191]    [Pg.53]    [Pg.53]    [Pg.75]    [Pg.80]    [Pg.361]    [Pg.14]    [Pg.25]    [Pg.9]    [Pg.676]    [Pg.995]    [Pg.900]    [Pg.375]    [Pg.12]    [Pg.34]    [Pg.35]    [Pg.198]    [Pg.201]    [Pg.628]    [Pg.629]   
See also in sourсe #XX -- [ Pg.90 , Pg.91 ]




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Alkali clusters, electron affinities

Boron hydrides electron-deficient clusters

Cancer clusters electronic workers

Carbon clusters electronic structure calculations

Cationic clusters electron

Cluster 9 Brain Cancers in Offspring of Electronics Workers

Cluster complexes, valence electrons

Cluster compounds Electron counting

Cluster compounds electron affinity

Cluster compounds electron-rich clusters

Cluster electron precise

Cluster electronic configurations

Cluster model electronic structure

Cluster valence electron

Cluster valence electron counts

Cluster-based electrons

Cluster-trapped electron

Clusters electron affinities

Clusters electron ionization

Clusters electron poor

Clusters electron poor transition metals

Clusters electron rich

Clusters electronic relaxation

Clusters polyhedron skeletal electron pair theory

Clusters skeletal electron pairs theory

Clusters valence electron deficiency

Clusters, metal electron counting

Correlation, electron Configuration interaction, Coupled-cluster

Counting electrons in metal clusters

Coupled Electron Pair and Cluster Expansions

Coupled-cluster electronic structure

Coupled-cluster theory, electron correlation

Coupled-cluster theory, electron correlation configuration interaction calculations

Coupled-cluster wave functions, derivatives electronic energy

Dianionic clusters electronic properties

Dinuclear clusters electronic configuration

Effects of Electron Correlations and Structure on Cluster Magnetism

Electron Affinities of Atomic Clusters

Electron Transfer Clusters

Electron affinity coupled-clusters

Electron clusters disjoint

Electron configuration metal clusters

Electron correlation coupled cluster approach

Electron correlation coupled-cluster methods

Electron correlation methods coupled cluster theory

Electron count cluster-fusion rule

Electron counting borane cluster compounds, 364

Electron counting cluster

Electron counting cluster hydrides

Electron counting main-group cluster fragments

Electron counting platinum clusters

Electron counting rule cluster valence electrons

Electron coupled cluster

Electron coupled cluster-method

Electron deficient cluster

Electron diffraction water clusters

Electron embedded cluster

Electron high nuclearity clusters

Electron metal clusters

Electron paramagnetic resonance clusters

Electron paramagnetic resonance iron-sulfur clusters

Electron to clusters

Electron transfer kinetics clusters

Electron-Poor (Hypoelectronic) Metal Carbonyl Clusters

Electron-binding energies, iron clusters

Electron-deficient borane and carbaborane clusters an introduction

Electron-deficient clusters boron-containing

Electronic MgXg clusters

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 behavior, platinum clusters

Electronic cluster formation

Electronic configurations cluster complexes

Electronic energy coupled-cluster waves functions

Electronic properties, hexanuclear clusters

Electronic shell alkali atom clusters, closing

Electronic states cluster-trapped

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

Electrons aqueous clusters

Embedded cluster model electronic states

Excited electronic states coupled-cluster

Excited electronic states, ultrafast cluster

Fe—S clusters as electron carriers

Free electron clusters

Group 5 metal halide clusters electronic structure

Group electron-deficient borane clusters

Hexanuclear clusters electronic structures

High-valence cluster electron configuration

Iron complexes, electron-transfer reactions clusters

Iron-sulfur cluster single-electron transfer

Iron-sulfur clusters electron transfer

Iron-sulfur clusters electron-transfer series

Isoelectronic cluster electron counting

Isoelectronic cluster skeletal electron count

Lead electron-deficient cluster

Lead electron-precise cluster

Metal cluster compounds electronic configurations

Metal clusters closed electronic structure

Metal clusters electron counting procedures

Metal clusters electronic conductivity

Metal clusters electronic effects

Metal clusters electronic model

Metal clusters free-electron theory

Metal oxide clusters electronic structures

Metal-carbonyl clusters skeletal bonding electrons

Metallic clusters electronic spectrum

Mingos cluster valence electron count

Mingos cluster valence electron count schemes

Molybdenum cluster compounds electronic structure

Neutral clusters electronic properties

Nickel clusters electronic properties

Niobium halide clusters electronic structure

Odd-even electron numbers and energy level statistics in cluster assemblies

Palladium clusters electronic properties

Palladium small clusters, electronic structure

Polyhedral skeletal electron pair theory transition metal clusters

Real-time dynamics of electron migration in a model water cluster anion system

Rules for Cluster Structure-Electron Counting Correlations

Scanning electron microscopy, studies supported metal clusters

Silver clusters electronic properties

Sodium clusters electronic properties

Sodium clusters electronic shell structures

Tetrahedral metal clusters, valence electron

Total valence electron counts in d-block organometallic clusters

Transition metal clusters as four-electron donor

Transition metal clusters electron deficiency

Transition metal clusters electronic spectra

Transition metal clusters skeletal electron counting

Transition metal clusters valence electrons

Valence electron counts listed for various cluster frameworks

Valence electron counts, iron clusters

Valence electrons in clusters

Wade electron counting rules borane-like cluster nomenclature

Water cluster electron diffraction pattern

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