Types atomic

Hehre W J, Stewart R F and Popie J A 1969 Seif-consistent moiecuiar-orbitai method i. Use of Gaussian expansions of Siater-type atomic orbitais J. Chem. Phys. 51 2657-64... 

Hehre, W.J. Stewart, R.F. Pople, J.A. Self-consistent molecular-orbital methods. I. Use of Gaussian expressions of Slater-Type Atomic Orbitals 7 Chem. 51 2657-2664, 1969. 

For each atom there are a maximum of five one-center two-electron integrals, that is (ssiss), (ssipp), (spisp), (ppipp), and (ppip p ), where p and p are two different p-type atomic orbitals. It has been shown that the extra one-center two-electron integral, (pp Ipp ), is related to two of other integrals by... 

For airblast-type atomizers, it has been speculated (33) that the Sauter mean diameter is governed by two factors, one controlled by air velocity and density, the other by Hquid viscosity. Equation 13 has been proposed for the estimation of equation 13, and B are constants whose values depend... 

Gaussian and other ab initio electronic structure programs use gaussian-type atomic functions as basis functions. Gaussian functions have the general form ... 

Self Consistent Molecular-Orbital Methods I. Use of Gaussian Expansions of Slater-Type Atomic Orbitals W. J. Hehre, R. F. Stewart and J. A. Pople The Journal of Chemical Physics 51 (1969) 2657-2665... 

Least squares representations of Slater-type atomic orbitals as a sum of Gaussian-type orbitals are presented. These have the special feature that... 

Oil burners Type Size range Dual-fuel capability Fuel type Atomizing Atomizing pressure viscosity (bar) (cS) Turndown ratio Flame characteristics Main applications... 

BOND LENGTHS (A) type atom nos. bond angles (DEGREES) TYPE atom nds. torsion ANGLES 1 (DEGREES) type ATOM NOS... 

By choosing different combinations of Hyps. 1 to 9, various "relations between the FeS2—P and FeS2—m type atomic arrangements may be deduced, but only those relevant to the judgement of the pair-reorientation model are presented here. The combination of Hyps. 1, 5, and 7 gives an expression... 

One of the special rotary atomizers worth mentioning is the windmill type atomizer. In this atomizer, radial cuts are made at the periphery of a disk and the tips of segments are twisted, so that the disk is actually converted into a windmill that can rotate rapidly when exposed to an air flow at aircraft flight speed. The windmill type atomizer has been demonstrated 1171 to be an ideal rotary atomizer for generating a narrow spectrum of droplet sizes in the range most suitable for aerial applications of pesticides at relatively high liquid flow rates. 

The above treatment of heteroatoms in terms of X-, Y-, and Z-type atoms was included in four books.4b 55,63,64... 

Y-type atoms are not shown explicitly. Asterisks indicate mesoaromatic systems. Numbers in brackets are the (x,y,z) triplet values corresponding to solutions of diophantine equations (Table 1). 

A further consequence of the foregoing discussion is a new definition generalizing the so-called me-soionic (mesomeric betaine) systems with two chains of odd-membered Y-type atoms separated by X- or Z-type atoms. Such systems are indicated by an asterisk in Table 1. Thus, 1,3-diborete 50 (Scheme... 

As seen in the above structures, carbon atoms with exocyclic C=W bonds (where W symbolizes an electron-withdrawing group such as O, NR, or S) count as Z-type atoms. Indeed, 4//-pyrone 56 and tropone 57 (Scheme 27) may be considered to be normal... 

Both cases with n = 0 and n = 1 in the Hiickel rule of 4n+2 jr-electrons can be achieved for four-member ed heterocyclic rings. However, the stability of the resulting system is low in either case, owing to ring strain, the adjacency of two X- or Z-type atoms, or the mesoaromatic character when such heteroatoms are not adjacent, as in 1,3-diborete. 

Five-membered heterocycles with two heteroatoms have the jr-electron deficiency of Y-type heteroatoms compensated by the jr-electron excessive character of the X-type atoms therefore, this category includes some of the most stable heterocycles. For example, NMR spectral data and chemical behavior (e.g., resistance to oxidation by potassium permanganate) suggest that pyrazole and imidazole have delocaliza-... 

Liebig, too, saw the aim of chemistry as the search not only to consolidate the truth of chemical proportions but to study the causes of the regularity and constancy of these proportions. Liebig took the cause of chemical action to lie in Newtonian-type atoms and forces of the Berzelian variety, that is, spherical atoms and electrical affinity forces. 31 This is a problem-solving tradition focused on atoms and powers, or mechanism and materialism.32... 

Randall et al. (Rl) examined some 60 liquids with a buret-type atomizer and positive dc voltage. They also concluded that atomization could not be achieved if the resistivity was greater than 1010 fi cm and became much poorer if the resistivity was less than 10s SI cm. Increased viscosity resulted in a coarser spray, especially for viscosities above 20 cp. Measurements of size distribution are reported which indicate mass median diameters larger than 20 microns. An optimum voltage of 25-40 kV was found at which the mass median diameter was a minimum. They also ran limited tests with glass capillary atomizers (<200 microns i.d.) for which they estimated droplet sizes were less than 10 microns when atomization was achieved. They give a... 

The first calculations on a two-electron bond was undertaken by Heitler and London for the H2 molecule and led to what is known as the valence bond approach. While the valence bond approach gained general acceptance in the chemical community, Robert S. Mulliken and others developed the molecular orbital approach for solving the electronic structure problem for molecules. The molecular orbital approach for molecules is the analogue of the atomic orbital approach for atoms. Each electron is subject to the electric field created by the nuclei plus that of the other electrons. Thus, one was led to a Hartree-Fock approach for molecules just as one had been for atoms. The molecular orbitals were written as linear combinations of atomic orbitals (i.e. hydrogen atom type atomic orbitals). The integrals that needed to be calculated presented great difficulty and the computations needed were... 

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