Orbital information index

From this definition, other indices are derived the bonding orbital information index ly... 

Information-theoretic indices, including the Shannon index, the chromatic information index, the orbital information index, the topological information superindex, the electropy index, and the Merrifield and Sinmions indices [13,14]. 

The first information index proposed as a measure of complepty of an - H-depleted molecular graph is the vertex orbital infonnation content 7orb> originally simply called topological infonnation content /top [Rashevsky, 1955 Trucco, 1956a Trucco, 1956b], defined as - mean information content. 

Other specific information indices are - orbital information indices, -> information connectivity indices, - indices of neighbourhood symmetry, information layer index,... 

World Patents Index DIALOG, ORBIT, Questel, STN Derwent Information Ltd. international limited bibliographic data patent families comprehensive English language abstracts of basic and some equivalent granted patents polymer and chemical stmcture indexing for subscribers drawings... 

Patent Citation Index DIALOG, Questel—ORBIT, STN Derwent Information Ltd. international examiners and inventors citations of eadier references and later citing patents Derwent tide, bibhographic, and family information... 

World Patents Index / APIPAT ORBIT Derwent Information Ltd. American Petroleum Institute international limited bibhographic data patent families comprehensive English language abstracts of basic patents aU Wodd Patents Index and APIPAT indexing for subscribers... 

Besides the worldwide WPI database, Derwent provides on the ORBIT system the USPatents database, a bibhographic file of patent front page and cl aim information for U.S. patents since 1971. Derwent also produces a biotechnology database, GENESEQ, that indexes sequence stmetures of proteins or nucleic acids disclosed specifically or genetically in patents. This database is searchable with special sequence software on the InteUiGenetics system, and is a new addition to STN s database catalog. 

These summarize topological information about a molecule with atomic properties [39]. A molecular E-state index is expressed as a sum of atomic E-state indices, which are composed of two parts. First is the intrinsic atomic part, and second is perturbation, which depends on its neighborhood (other atoms in the structure). The intrinsic part includes information about the a- and 7r-orbitals, lone pairs, hydrogen atoms attached to heavy atoms, and the principal quantum numbers of valence electrons. The perturbation part is a sum of all other atomic parts modified by fimction, which descends with distance. 

In the same way as the a, -separation has been performed, one can proceed to a cr, rr-separation.52 This separation has been used to evaluate the aromaticity of organic molecules and clusters. An index of aromaticity was proposed using a scale based on the bifurcation analysis of the ELF constructed from the separated densities. In principle, the total ELF has no information about tt and cr bonds, it depends only on the total density. Hence, the ELF does not show clear differences between both kinds of bonds. However, the topological analysis over separated densities, ones formed by the rr-orbitals and the other ones formed by the cr-orbitals, yields the necessary information.52 Of course, this is possible only for the molecules which present the cr, tt symmetries, i.e. planar molecules. The bifurcation analysis of the news ELFW and ELFCT can be interpreted as a measure of the interaction among the different basins and chemically, as a measure of electron delocalization.45 In this way, the tt and a aromaticity for the set of planar molecules described in the Scheme 1 has been characterized.52... 

In this section we discuss index theory, a method that provides global information about the phase portrait. It enables us to answer such questions as Must a closed trajectory always encircle a fixed point If so, what types of fixed points are permitted What types of fixed points can coalesce in bifurcations The method also yields information about the trajectories near higher-order fixed points. Finally, we can sometimes use index arguments to rule out the possibility of closed orbits in certain parts of the phase plane. 

PharmSearch. Institut National de Propriete Industrielle, Paris. Pharmaceutical patents indexed by INPI, the French Patent Office, with chemical structures searchable in the Mar-kush DARC system on Questel-Orbit. Abstracts, bibliographic information, and proprietary indexing from one patent per family. PharmSearch shares the topological chemical structure... 

Many libraries also have available the Dialog, BRS, Orbit, and STN International Retrieval Services, which are online computer information retrieval services. All the Predicast data, the Applied Science and Technology Index, CA Search, Chemical Industry Notes, CSCORP, and Kirk-Othmer are searchable through these services. 

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