Ethylene molecular geometry

Pappalardo, R. R., Sanchez Marcos, E., Ruiz-Lopez, M. F., Rinaldi, D. and Rivail, J. L. Solvent effects on molecular geometries and isomerization processes A study of push-pull ethylenes in solution, JAm.Chem.Soc., 115 (1993), 3722-3730... 

Figure 2.34. Symmetry-resolved experimental C Is XAS of ethylene adsorbed on Cu(l 10) (solid lines) and Ni(110) (dashed lines). The coordinate system and molecular geometry used for the calculations are shown in the inset. From Ref. [85].

The molecular geometry of ethylene oxide has been studied primarily by means of electron diffraction and microwave spectroscopy, together with classical techniques of dipolo-moment measurement. 

The molecular geometry of the parent cis-1,2-di-9-anthrylethylene 38a has not been established by X-ray diffraction, but crystal structure analyses of several 1,2-substituted cis-dianthrylethylenes 38 are available. Depending on the spatial demand of the substituents R and R, the planes of the anthracene moieties are twisted out of the plane of the ethylene by 59-84° [80],... 

As for cis- and trans- l-(9-anthryl)-2-phenylethylenes (9-styrylanthra-cenes) 68a and 69a, differences in their ground state molecular geometry in terms of angles between the planes of the three jt-systems, viz. anthracene, ethylene, and phenyl, as revealed by X-ray diffraction analyses, are relatively small (see Table 14). The major geometrical difference between the two isomers is found in the angle between the anthracene and ethylene ir-systems. 

Recall that in the VSEPR model a double bond acts as one effective pair. Thus in the ethylene molecule each carbon is surrounded by three effective pairs. This model requires a trigonal planar arrangement with bond angles of 120 degrees. What orbitals do the carbon atoms use in this molecule The molecular geometry requires a planar set of orbitals at angles of 120 degrees. Since... 

R. R. Pappalardo, E. S. Marcos, M. F. Ruiz-Lopez, D. Rinaldi, and J.-L. Rivail, /. Am. Chem. Soc., 115, 3722 (1993). Solvent Effects on Molecular Geometries and Isomerization Processes A Study of Push-Pull Ethylenes in Solution. 

A FIGURE 9.22 Trigonal-planar molecular geometry of ethylene. The... 

A Figure 9.22 Trigonal-planar molecular geometry of ethylene. The double bond is made up of one C—Co- bond and one C—Ct7 bond. 

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