Multielectron coordination

Such bidentate chelation is found to be favored over monodentate complexation in many cases, this being the so-called chelate effect.  

Let us first consider the eight-electron Ir+ ion as a prototype two-pair-acceptor species, forming 12e IrL2+ complexes. Optimized Ir(ligand)+ structures for the monodentate and bidentate ligands of Fig. 4.85 are shown in Fig. 4.86. As shown 

3 Parenthesized values refer to the middle C atom in the symmetry plane. 

Ir+ (see Fig. 4.86) metal charge Qm, bonding hybrid Iim, percentage polarization toward the metal atom (%po1m), and NRT bond order 6ml 

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Considering fi, v = 4f and 5d, eq 1 is a matrix with 12 by 12 elements, important for computation of the intensities of the transitions by distributing its elements over the whole manifold of the multielectron wave function. Considering the actual centrosymmetric Dw coordination of Eu2+, only the 7 by 5 elements corresponding to the off-diagonal (i//4fldah//sj) block... 

It has been our goal for some time to run photochemical energy storage reactions without relay molecules or separate catalysts. We have concentrated on the photochemistry of polynuclear metal complexes in homogeneous solutions, because we believe it should be possible to facilitate multielectron transfer processes at the available coordination sites of such cluster species. 

As the electron orbitals of the isolated Fe coordination polyhedra must be converted to the multielectron states found in the actual oxides,... 

A much more positive value of E° = —0.88 V is estimated in aqueous solution at pH >11 by using short-time pulse techniques [7, 8], The aqueous electrochemistry of Tc04 is complex. Under alkahne conditions, it is proposed that the protonation of Tc04 and/or the expansion of its coordination shell follows Eq. (1) and produces a more easily reduced Tc(VI) species, resulting in a multielectron transfer [8]. The subsequent reduction can... 

In the Bom interpretation (Section 4.2.6) the square of a one-electron wavefunction ij/ at any point X is the probability density (with units of volume-1) for the wavefunction at that point, and j/ 2dxdydz is the probability (a pure number) at any moment of finding the electron in an infinitesimal volume dxdydz around the point (the probability of finding the electron at a mathematical point is zero). For a multielectron wavefunction T the relationship between the wavefunction T and the electron density p is more complicated, being the number of electrons in the molecule times the sum over all their spins of the integral of the square of the molecular wavefunction integrated over the coordinates of all but one of the electrons (Section 5.5.4.5, AIM discussion). It can be shown [9] that p(x, y, z) is related to the component one-electron spatial wavefunctions ij/t (the molecular orbitals) of a single-determinant wavefunction T (recall from Section 5.2.3.1 that the Hartree-Fock T can be approximated as a Slater determinant of spin orbitals i/qoc and i// /i) by... 

The multielectron wavefunction T is a function of the spatial and spin coordinates of all the electrons. Physicists say that T for any system tells us all that can be known about the system. Do you think the electron density function p tells us everything that can be known about a system Why or why not ... 

For MCCC - the presence of multielectron multicenter coordination bonds. 

Another question is which one, the bis coordination of O2 to two CoP centers or the electronic effects induced by the peripherally coordinated Ru(III)Ru(III) Ru(II), would be responsible for the cobalt porphyrin activation in the multielectron-transfer process. In fact, considering that the Co(4-TCPyP) films are formed by stacks of supermolecules, it is not possible a priori to rule out the first hypothesis. This problem was solved by repeating the experiments using the electrostatic assembled Co(4-TCPyP)/ZnTPPS films in which the bis coordination of dioxygen to two cobalt porphyrin centers is not possible (176). The catalytic behavior is reproduced in the ion pair film, confirming that the activation is mainly due to electronic effects induced by the peripheral ruthenium clusters, in synergistic association with their normal role as intramolecular multielectron source. 

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