A molecular orbitals, energy

Construct and interpret a molecular orbital energy-level diagram for a homonuclear diatomic species (Sections 3.9 and 3.10). 

For each of the following, draw a molecular orbital energy level diagram and give the bond order. Tell whether the species would be more or less stable after gaining an electron, (a) 02+ (b) CN (c) S2 (d) NO (e) Be2+. 

Construct a molecular orbital energy level diagram for the SO molecule and speculate on the nature of the bond and other characteristics of the molecule. 

Sketch a molecular orbital energy-level diagram. Use the same diagram to save time, unless it becomes too messy. 

It will be realized that the values of n and m of A will depend on the metal site symmetry and n will only have even values for states of the same parity. In a frequently overlooked paper Eisenstein [554] tabulated the symmetry classifications of the metal ion and ligand orbitals for most of the point group site symmetries of interest. These classifications are often very useful in constructing a molecular orbital energy diagram. Predictions regarding the number and classification of the excited electronic states can then easily be made with the help of such diagrams. We will, however, resist the temptation to reproduce those tables here, in order to conserve space, as they are easily available. 

FIGURE 3.31 A molecular orbital energy-level diagram for the bonding and antibonding molecular orbitals that can be built from two s-orbitals. The signs of the s-orbitals are depicted by the different shades of blue. 

Draw a molecular orbital energy-level diagram and determine the bond order expected for each of the following species (a) Li2 (b) Li2+ (c) Li2 . State... 

Calculations were finally performed to investigate a mechanism of the methane production increase by CO2 injection to coal seam. Coal includes carbon, hydrogen, and other elements, as Figure 25.14 depicted a simple model of a coal surface. Figure 25.27 shows a molecular orbital energy level diagram for this... 

Fig. 6.10. Electronic structure of pyrite (a) molecular-orbital energy-level diagram (modified after Burns and Vaughan, 1970) (b) schematic one-electron energy-band diagram. Numbers in brackets refer to the number of electron states per molecule available. is the Fermi level hatched bands are filled with electrons (modified after Either et al., 1968 Goodenough, 1972).

Fig. 6.17. Electronic structure models for FeS (a) molecular-orbital energy levels for the FeSj" octahedral cluster calculated using the MS-SCF-Za method, for low-spin Fe + (singlet, as in pyrite) and high-spin Fe + (quintet) states (after Tos-sell, 1977) (b) electron structure model for pyrrhotite based on calculated energy levels for the FeSe " cluster (from Tossell, 1977) and sulfur Ai(3 emission and K absorption spectra (Diagram after Sakkopoulos et ah, 1984) (c) schematic energy-level diagram for the troilite form of FeS (after Goodenough, 1967).

Prepare a molecular orbital energy level diagram for SH , including sketches of the orbital shapes and the number of electrons in each of the oibitals. If a program for calculating molecular orbitals is available, use it to confirm your predictions or to explain why they differ. 

The ion H3 has been observed, but its structure has been the subject of some controversy. Prepare a molecular orbital energy level diagram for H3, assuming a cyclic structure. (The same problem for a linear structure is given in Exercise 5-4.)... 

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