Charge distributions, calculated

MO calculations at the 6-3IG level have been done on both acrolein and aminoethylene. The resulting MOs were used to calculate charge distributions. Figure 1.26 gives the 7t-electron densities calculated for butadiene, acrolein, and aminoethylene. Inclusion of the hydrogen and a orbitals leads to overall charges as shown. These charge distributions result from a polarization which is counter to the n polarization. 

CH3OH, has a polar covalent C-0 bond, and (b methyl-iithium, CH3Li, has a polar covalent C-Li bond. The computer-generated representations, called electrostatic potential maps, use color to show calculated charge distributions, ranging from red (electron-rich ... 

The calculated charge distributions for the parent and the a- and -substituted vinyl cations are as follows (163) ... 

In the complex xenon functions as a n-donor toward Au2+. This is reflected in the calculated charge distribution within the cation, where the main part of the positive charge resides on the xenon atoms. Relativity plays a large role in stabilizing this and other predicted Au—Xe compounds about half of the Au—Xe bonding energy comes from relativistic effects.1993... 

Assuming that the enone component of the oriented 77-complex is in its n -> 77 excited state and the olefin is situated above the a,/9 double bond of the enone, one can explain the mode of addition by the calculated charge distribution of the n - 77 excited state ... 

Table 11.5. Calculated Charge Distributions for Positions 2 and 3 of 2,3-Dimethoxy-6- (and 5-) Nitronaphthalenes...

AMI Calculated Charge Distribution (e) and Frontier Orbital Energies ( ) and Coefficients for 4- and 5-Aminoimidazoles (179) and (180)... 

Pfeiffer and Jewett (1970), however, have made ab initio calculations on the ethyl cation and report the charge distributions in Figure 4b for the most stable ethyl ion. Their calculations agree with Hoffmann s in predicting that the classical ethyl structure is more stable than a bridged structure, but their calculated charge distribution is entirely different. 

Figure 3 Calculated charge distribution and overlap populations for smoothed geometry of cyclo-...

TABLE 5. MINDO/3 calculated charge distribution for 1-dimethylamino- and 2-dimethylamino-1,3-butadienes"... 

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