Modern Terminology

Stereogenic Interconverting two ligands center produces a new stereoisomer 

Illustration of the concept of the stereogenic center in the context of carbon. Whether in a chiral molecule like 2-butanol or an achiral molecule like meso-tartaiic acid, interconversion of two ligands at a stereocenter produces a new stereoisomer. 

Tartaric acid has two stereogenic centers and exists as three possible stereoisomers. This is an exception to the norm. Typically, a molecule with n stereogenic, tetracoordinate carbons will have 2 stereoisomers-2 diastereomers that each exist as a pair of enantiomers. For example, a structure with two stereogenic centers will exist as RR, SS, RS, and SR forms. In tartaric acid the RS and SR forms are identical—they are both the meso form—because C2 and C3 have the same ligands. 

Total Synthesis of an Antibiotic with a Staggering Number of Stereocenters 

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State Multiplicity Symr Modern Terminology netry Mulliken s Terminology Transition... 

The three basic methods introduced by Hylleraas in his work on the He series have in modern terminology obtained the following names (a) Superposition of configurations (b) Correlated wave functions (c) Different orbitals for different spins. The first two approaches are developed almost to the full extent, whereas the last method is at least sketched in the 1929 paper. 

In the preliminary discussions in the 1929 paper (Eq. 11), Hylleraas also discussed some lower approximations and pointed out the importance of a configuration where there exist one "inner electron and one "outer electron. In modern terminology, this corresponds to a splitting of the closed shell (Is)2 into an open shell (Is, Is), or to the use of "different orbitals for different electrons. Hylleraas reported the good result E = —2.8754 at.u. for such a configuration, but pointed also out that a "correlated wave function of the form... 

This is not a historical paper modern terminology is intentionally being used. 

Modern terminology defines A as the absorbance, a as the absorptivity, b as the optical path length and c as the concentration. In the second equation s represents the molar absorptivity. Table 5.4 compares these terms. 

Direct initiation is the term used for the initiation of a CP by a metal halide without a co-catalyst (co-initiator in modern terminology). 

We envisage the propagation step as the addition of the components of the ester across the double bond of the monomer in modern terminology this is an insertion reaction. Whether this reaction occurs through a 4-centre or a 6-centre transition state, as shown below, is not clear. 

It now remains to place the concept of an ester as an active species into a wider chemical context, with special reference to polymerisation catalysts. Sinn and Patat [39] have emphasised the distinction between monofunctional and bifunctional catalytic systems and this distinction is obviously and necessarily related to the idea, explained above, that there is a difference in kind between polarised molecules and the ions which can be formed from them. Whereas the carbonium and other cations as reactive species are monofunctional, the esters evidently belong to the class of bifunctional catalysts their mode of action - the addition of their constituent parts across a double bond - is, in modern terminology, an insertion reaction. In this context, we must note the important... 

Compressors are any machines that raise the pressure above the levels for which fans are used. Thus, in modern terminology they include blowers. 

In modern terminology, the word detergent refers to a synthetic variety and is not derived from natural fats and oils as are soaps... 

In his classic paper on electric networks, G. Kirchhoff[38] (1847) implicitly established the celebrated Matrix-Tree-Theorem which, in modern terminology, expresses the complexity (i.e., the number of spanning trees) of any finite graph G as the determinant of a matrix which can easily be obtained from the adjacency matrix of G. Simple proofs were given by R. L. Brooks, C. A. B. Smith, A. H. Stone and W. T. Tutte [39] (1940), H. Trent [40] (1954), and H. Hutschenreuther [41] (1967) (for relations between the complexity and the spectrum of a graph see Ref. [36] pp 38, 39, 49, 50). 

The axioms that underpin any theory of chemical interaction were clearly stated by Kekule, in the middle of the 19th century, as a theory of chemical affinity [16]. Restated in modern terminology ... 

In modern terminology the messenger RNA would collect the amino acid of peptides represented by A + B + C, etc., and deposit them on a ribosome where they would be assembled to give rise to A + C, or albumin AC, )3-globulin and various proportions of B + C in addition to A to give rise to a continuous system. A, B, and C are model peptides, but the system is not necessarily limited to these three, in that these three are not discrete peptides but rather areas on the template by this mechanism common peptides should appear in high incidence among the serum proteins. 

Volmer [iv]. In modern terminology the result is given by Fletcher [v] as... 

Action. This technical term is a historic relic of the 17th century, before energy and momentum were understood. In modern terminology, action has the dimensions of energyxtime. Planck s constant has those dimensions, and is therefore sometimes called Planck s quantum of action. Pairs of measurable quantities whose product has dimensions of energyxtime are called conjugate quantities in quantum mechanics, and have a special relation to each other, expressed... 

Asphalt suffers from the uncertainty of meaning of the Greek word asphaltos and of its correspondence to related words in ancient Near Eastern languages (2). In modern terminology the term refers to a natural or manufactured mixture of mineral fines and bitumen. 

This is a completely new edition of what has become the standard reference text in the field of adverse drug reactions and interactions since Leopold Meyler published his first review of the subject 55 years ago. Although we have retained the old title, Meyler s Side Effects of Drugs, the subtitle of this edition, The Encyclopedia of Adverse Drug Reactions and Interactions, reflects both modern terminology and the scope of the review. The structure of the book may have changed, but the Encyclopedia remains the most comprehensive reference source on adverse drug reactions and interactions and a major source of informed discussion about them. 

There has been considerable discussion of the situation in regard to the ionic structures. About fifty years ago Michaelis978,983-984 1002 1003 proposed (XIX) as the structure for 1,2-disubstituted pyrazolinones. In modern terminology this could correspond to structure (XIV). 

According to von Weizsacker (in Plaass 1994,174) the MAdN deals with the conditions under which— in modern terminology—the assignment of physical meaning to mathematical concepts is possible. ... 

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