Electronic structure ground state configurations

The energy-level structure of CO2 is shown in Figure 6.28. With 16 valence electrons, the ground-state configuration of CO2 is (cr ) (cr ) (crs) (crp) (7r, 7Ty) (7if, Tif). The bond order for each CO bond is 2 because there is a cr bond and a tt bond between each pair of atoms. 

As mentioned above, the information contained in STM images pertains principally to the electronic structure of the surface, and (as for most types of microscopy) STM provides no direct insight into the chemical identities of structures. This lack of chemical specificity often makes it difficult to relate the observed structures of complex clusters, molecular adsorbates, or reaction intermediates to their chemical nature and conformation on the surface. Theoretical electronic-structure calculations are therefore commonly employed to assist in the interpretation of STM results. The theoretical calculations provide complementary information about the possible ground-state configurations of samples and can be used to generate fairly accurate simulations of STM images. 

Most of the nickel compounds in the solid state and almost all in aqueous solution contain the metal in the oxidation state +2, which, by consequence, can be considered the ordinary oxidation state for nickel in its compounds. The electronic structure and stereochemistry of nickel(II) were reviewed in 1968.6 The most stable electronic configuration of the free Ni ion is [Ar]3d8 which is also the ground state configuration in its complexes. The overwhelming majority of nickel(II) complexes have coordination numbers of four, five and six. Complexes with coordination numbers of three, seven and eight are still quite rare. 

Ground-state configuration and electronic structure of the monomeric uranium(III) alkyl [t 5-(CH3)5C5]2UCF[[Si(CF[3)3]2 were investigated and reported... 

In contrast to these spin-allowed transitions in Ti3 and Fe2+, only spin-for-bidden transitions are possible in 3d15 cations such as Fe3+ and Mn2+ when they are coordinated to oxygen ligands. The electronic structures of these cations are such that in their ground-state configurations, (r2g)3(eg)2 represented by... 

The electronic structure of SO2 has been the subject of several theoretical studies which have provided a basis for interpretations of UV and photoelectron spectroscopic measurements These will not be reviewed in detail here since they all agree on those features which are important for a qualitative understanding of transition metal complex formation. The ground state configuration obtained from the extended Hiickel approach, for example, is (Iai) (lb2) (2ai) (lbi) (3ai) (2b2) (la2) (3b2) (4ai) (2bi) (4b2) (5ai) using 2 s, 2 p oxygen orbitals and 3 s, 3 p sulfur orbitals as a basis. The salient features from the M-SO2 bonding standpoint are the HOMO (4ai) and the LUMO (2bi), depicted in Fig. 2. These two orbitals can be described qualitatively as follows ... 

The ground state configuration for Ni"(g) is given by Hotop and Lineberger (2, 4) and Rosenstock et al. (5) and Masey (6). The fine structure separation has been measured experimentally be laser photodetachment electron spectrometry (3) and is that recommended by Hotop and Lineberger (2). 

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