Calculations density

Here, and Lj are local indices having the form shown in Eq. (5), where lo is a constant characterizing the ith atom (in some cases the atom valence can be used to this end), Nh is the number of attached hydrogen atoms and is the charge density calculated by some fast method such as the Marsili-Gasteiger charge calculation method [7]. 

We have the makings of an iterative computer method. Start by assuming values for the matr ix elements and calculate electron densities (charge densities and bond orders). Modify the matr ix elements according to the results of the electron density calculations, rediagonalize using the new matrix elements to get new densities, and so on. When the results of one iteration are not different from those of the last by more than some specified small amount, the results are self-consistent. 

The commercially accepted value has been given. Measured values and density calculations from x-ray data show some variations. To convert MPa to psi, multiply by 145. 

Electron-density calculations for quinazoline (which has no symmetry) vary markedly with the method used. The diagram (6) has the same bases as that given for pyrimidine above it will be observed that the 2- and 4-positions in quinazoline are comparable with the corresponding positions in pyrimidine and that the aromatic carbon atoms (C-5-C-8) in quinazoline are roughly comparable with C-5 in pyrimidine (67MI21300). The dipole moment of quinazoline does not appear to have been measured, but that of 2-methylquinazo-line is 2.2 D. 

Apart from the general study by Wait and Wesley on azanaphthalenes, including most of the pyridopyridazines (66JSP(19)25), more specialized studies have attempted to relate charge density calculations to various chemical and physical properties, with greater success in the latter case. 

H-Dibenz[6,e][l,4]oxaborin UV spectrum, 1, 643 6H- Dibenz[c, e][l, 2]oxaborins as antioxidants, 1, 663 Dibenzoxanthenes charge density calculations, 3, 576 Dibenzoxanthenium salts X-ray studies, 3, 625 Dibenzoxanthones... 

Beyer synthesis, 2, 474 electrolytic oxidation, 2, 325 7r-electron density calculations, 2, 316 1-electron reduction, 2, 282, 283 electrophilic halogenation, 2, 49 electrophilic substitution, 2, 49 Emmert reaction, 2, 276 food preservative, 1,411 free radical acylation, 2, 298 free radical alkylation, 2, 45, 295 free radical amidation, 2, 299 free radical arylation, 2, 295 Friedel-Crafts reactions, 2, 208 Friedlander synthesis, 2, 70, 443 fluorination, 2, 199 halogenation, 2, 40 hydrogenation, 2, 45, 284-285, 327 hydrogen-deuterium exchange, 2, 196, 286 hydroxylation, 2, 325 iodination, 2, 202, 320 ionization constants, 2, 172 IR spectra, 2, 18 lithiation, 2, 267... 

UV spectra, 3, 599 xanthone synthesis from, 3, 840 Xanthydryl chloride xanthone synthesis from, 3, 840 Xanthyletin synthesis, 3, 743, 804 Xanthylium laser dye synthesis, 3, 865 Xanthylium salts aromaticity, 3, 641 charge density calculations, 3, 576 C NMR, 3, 592 H NMR, 3, 585 mass spectra, 3, 620 reactions... 

Sufficient charge must be available to supply the required critical surface charge density. Calculations show that 50-pound plastic bags and plastic lined 55-gallon drums are too small to represent a credible risk. 

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. 

S. H. Vosko, L. Wilk and M. Nusair, Accurate spin-dependent electron liquid correlation energies for local spin density calculations a critical analysis, Canadian J. Phys., 58,1200 (1980). 

Repeat your analysis fox phenoxy radical. Instead of charge, focus on the spin density. Calculate the delocalization energy using phenoxy radical at phenol geometry. Is it of the same order of magnitude as that for phenoxy anion Explain. 

The electron density calculated from a wave function is given as the square of the function, The reduced density matrix of order y, is defined as ... 

FMO calculations using the MNDO method and electron-density calculations were performed to establish which calculations are in agreement with the experimentally observed regioselectivity of the SnH amination of some nitronaphthyridines (see Section III,B). 

Electron density calculations of the parent unsubstituted 1,2,4-tri-azolo[l,5-c]pyrimidine suggested that N4 and N6 caused a decrease of the... 

Although electrophilic substitution in these compounds is difficult, bromination of pyridyl[2,3-bromo derivative, in accord with charge density calculations [73HC(27)968]. it is likely that this product formed as a result of HBr elimination from a 3,4-dibromo... 

Following Vincent and Radom s comprehensive ab initio study (1978), Escudero et al. (1985) also performed ab initio calculations at the STO-3G level for seven 4-substituted benzenediazonium ions. For the unsubstituted benzenediazonium ion, the optimized geometries are the same as in Figure 4-1 (I). For charge density calculations another population analysis method was used (Escudero and Yanez, 1982), and this gave results different from those of Vincent and Radom. However,... 

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