INDO intermediate neglect of differential

The INDO (Intermediate Neglect of Differential Overlap) differs from CNDO in the treatment of one-center exchange integrals. The CNDO (Complete Neglect of Differential Overlap) treatment retains only the two-electron integrals (p.p. vv) = The Yj y are... 

To confirm equation (4), we used the FPT (Finite Perturbation Theory) INDO (Intermediate Neglect of Differential Overlap) method (39) to calculate the Jqjj for various values of torsion angles. A comparison of the experimental and calculated values is plotted in Figure 5. 

Another more successful MO approach, referred to as INDO (intermediate neglect of differential overlap), avoids the average electronic energy approximation [115]. Its concept is a self-consistent field perturbation calculation. The INDO approach permits computation of one-bond carbon-13 coupling constants. The results obtained for JCH agree well with the experimental data for hydrocarbons and molecules with — F, —OR,... 

Conventionally, there are three levels of integral approaches CNDO (complete neglect of differential overlap), INDO (intermediate neglect of differential overlap), and NDDO (neglect of diatomic differential overlap). The last is the best of the approximations since it keeps the superior multipoles of charge distributions in the two-center interactions (unlike the others that shorten after the monopole). 

More recently gas-phase nitration was treated theoretically with MNDO (modified neglect of diatomic differential overlap) and INDO (intermediate neglect of differential overlap) self-consistent field calculations (34). Electron transfer and radical-pair recombination were favored for the nitration of toluene and the xylenes but not for nitrobenzene, for which a classical nitration route via a tt complex was favored. The calculations could not make a distinction between the two routes in the nitration of benzene. More information is needed about these coupling reactions and how they differ in the gas and heterogeneous-solution phases. 

Ultraviolet Spectra. A comparison of UV spectra for phthalazines and related systems has been prepared and discussed in a comparative way. " The electronic spectra for phthalazine and other azanaphthalenes have been calculated by a modified INDO (intermediate neglect of differential overlap) method. ... 

Estimates of the geometry of substituted radicals can be obtained from analysis of species labeled with Fessenden and Schuler determined that the anglle F-C-F in the trifluoromethyl radical is 111.1° (very nearly sp hybridization) and that increasing fluorine substitution causes the radicals to go from planar, sp2 hybridization for CHj to nearly tetrahedral, sp hybridization for "CF3. This conclusion is consistent with results of INDO (intermediate neglect of differential overlap) calculations Figure 4.9 shows the geometries of fluoromethyl radicals calculated by this method. 

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