Ethane electronic structures

The substitution system of nomenclature should be viewed as showing only how atoms are connected and not as indicating the precise electronic structure. Thus -adsorbed ethylene is one representation of 1,2-diadsorbed ethane. 

R. S. Mulliken, /. Chem. Phys., 3, 517 (1935). Electronic Structures of Polyatomic Molecules. IX. Methane, Ethane, Ethylene, Acetylene. 

The reaction of 1 -benzyl- 1,4-dihydronicotinamide (BNAH) with a series of 1,1-di-para-substituted-phenyl-2,2-dinitroethylenes in oxygen-saturated acetonitrile produced various amounts of the corresponding ethanes and diaryl ketones depending on the electronic structure of the substituent groups, thereby indicating a spectrum of behaviour intermediate between polar and SET mechanisms (Scheme ll).261... 

Transition metal derivatives assume p-p1 rj1 bridging modes which are assigned electronic structures H, I or J (Chart 3) on the basis of the central C-C separation, which can be related to those in ethyne (1.21 A), ethene (1.34 A), or ethane (1.53 A), respectively. 

H3NBH3 is isoelectronic with ethane, H2NBH2 is isoelectronic with ethylene, andHNBH is isoelectronic with acetylene. Derive the band structure and the DOS for planar poly- -BHNH- (isoelectronic to polyacetylene) with a single B-N distance and predict its conductivity and stability with respect to a Peierls distortion. Only consider the tt electronic structure. 

The CND0/S3 model has been applied to evaluate the electronic structure of a large number of aromatic hydrocarbons including m-xylene (12), p-xylene (12), l,4-dis(trifluoromethyl) benzene (12), 1,2 di(p-tolyl)ethane (1 ), [2.2]-paracyclophane (1 ), pseudopara-dicyano [2.2]paracyclophane (1 ), pseudo-para-dichloro [2.2]paracyclophane (1 ), 1,1,2,2,9,9,10,10 octaflu-... 

Write electronic structures for hydrogen iodide, HI hydrogen selenide, HgSe phosphine, PHg, arsenic trichloride, AsClg chloroform, HGCI3 ethane, C2H3. 

Throughout the studies discussed above, there has been a close interplay between structural measurements and development of theoretical models of molecular electronic structure. Lipscomb s contributions have included topological description of the boron hydrides and fundamental theory. Several coworkers contributed in this area, but most notable is the work with Roald Hoffmann, which changed the way chemists approach the theory of molecules of interesting complexity (see, e.g., the comments in (2(5)). The extended Huckel method was developed in the Lipscomb s group by several people, including especially L. L. Lohr, Jr., and Roald Hoffman (see Roald s recollections in Current Contents Citation Classic, May 8, 1989). Although the method probably contributed more to chemistry than any other method imtil very recently, Lipscomb recalled decades after he introduced it that this method received intense criticism, even denouncement. More exact theory led to the first correct calculation of the rotational barrier in ethane (with R. M. Pitzer in 1963). 

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