Parr method

Exhaustive oxidation of sulphones to sulphate using a mixture of potassium chlorate, sodium peroxide and sugar in a bomb has also been recommended220. This procedure is known as the Parr method and produces a mixture of soluble alkali sulphates. 

Parr method 995 Pauling s electronegativities 561 Penicillin sulphoxides epimerization of 750 synthesis of 246 Peptides 854, 864-866... 

Fig. 7.15 is constructed from reactivity diagrams of aromatic hydrocarbons already published. The reactivity of fluoranthene has often been investigated in detail from both, the experimental and theoretical aspects 116>. The values of /rE> calculated by the Pariser-Parr method (SCF) 117> as well as by the Hiickel MO (HMO) modified by considering... 

Henderson-Hasselbalch equation lahn-Teller effect Lee-Yang-Parr method Lineweaver-Burk method Mark-Houwink plot Meerwein-Ponndorf theory Michaelis-Menten kinetics Stem-Volmer plot van t Hoff-Le Bel theory Wolff-Kishner theory Young-Laplace equation Ziegler-Natta-type catalyst... 

By the middle of the 1960s, computers had improved, but they were still incredibly slow by today s standards. Therefore, the quantum chemistry of the time was dominated by semiempirical methods, such as the Pople-Pariser-Parr Method, the Wolfsberg-Helmholtz Method, and the Extended Hiickel Method. 

J.D. Hamill and A.J. Parr Methods for Production of Alkaloids in Root Cultures... 

It must also be pointed out that the charge is more negative in the ortho than in the para position when the Pariser and Parr method is used. This result seems in agreement with recent measurements of these charges based on n.m.r. experiments . Finally, the contribution... 

The electronic spectrum of aniline has been analyzed, using wave-mechanical methods, by various authors - . The self-consistent field method which has been presented in section I and used in section II to describe the ground state of this molecule can also be used to represent its electronically excited states. For practical reasons it is necessary to introduce the lcao approximation and either the Hiickel or the Pariser and Parr method is used. Furthermore, the virtual orbitals approximation is added. Let us consider the eigenfunctions 77j of the self-consistent field operator A " corresponding to the ground state of aniline in the lcao approximation. They obey the equation... 

The Pariser-Pople-Parr method is the simplest implementation of the self-consistent field method. Like the Hiickel method, it treats only the electrons in delocalized pi orbitals in planar molecules and represents these orbitals as linear combinations of basis functions that include only the unhybridized p orbitals. All overlap integrals are assumed to vanish, as in the Hiickel method, but not all of the integrals representing electron-electron repulsions are assumed to vanish. Two notations are used for these integrals ... 

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