812. A simple MO–LCAO method for the calculation of charge distributions in saturated organic molecules

Re, Giuseppe Del

doi:10.1039/jr9580004031

Cited by 357 publications

(100 citation statements)

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“…Molecular connectivity was calculated according to Kier and Hall (16), a sigma charge according to del-Re (17), and geometric descriptors from atomic coordinates.…”

Section: Methodsmentioning

confidence: 99%

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Pattern Recognition Analysis of a Set of Mutagenic Aliphatic N-Nitrosamines

Nesnow¹,

Langenbach²,

Mass³

1985

Environmental Health Perspectives

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A set of 21 mutagenic aliphatic N-nitrosamines were subjected to a pattern recognition analysis using ADAPT software. Four descriptors based on molecular connectivity, geometry and sigma charge on nitrogen were capable of achieving a 100% classification using the linear learning machine or iterative least squares algorithms. Three descriptors were capable of a 90.5% and two descriptors of a 85.7% overall correct classification. Three of the four descriptors were each capable of classifying 15 of the 16 active chemicals while it required three of the four descriptors to classify correctly two of the five inactive chemicals. These results are in concert with previous observations that molecular connectivity, geometry, and sigma charge on nitrogen are powerful descriptors for separating active from inactive mutagenic and carcinogenic N-nitrosamines.

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“…Molecular connectivity was calculated according to Kier and Hall (16), a sigma charge according to del-Re (17), and geometric descriptors from atomic coordinates.…”

Section: Methodsmentioning

confidence: 99%

“…The 21 N-nitrosamines ( (17) in the presence of primary hamster hepatocytes from Syrian golden hamsters according to previously published procedures (1,2,11). The mutation locus selected was ouabain resistance.…”

Section: Data Setmentioning

confidence: 99%

Pattern Recognition Analysis of a Set of Mutagenic Aliphatic N-Nitrosamines

Nesnow¹,

Langenbach²,

Mass³

1985

Environmental Health Perspectives

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show abstract

“…Subsequently, Veillard and Pullman [80] produced π-electron calculations using the semi-empirical antisymmetrized molecular orbital (ASMO) self-consistent-field (SCF) method [81,82]. Later, Bradley, Lifson and Honig [83] used united Veillard-Pullman π charges with σ-charges determined by the method of Del Re [84] to get a set of net charges summarizing both σ and π contributions. To eliminate the shortcomings in these methods Rein et al [85] proposed the iterative extended Hückel method which led to further improvement.…”

Section: Bmentioning

confidence: 99%

Role of quantum chemical calculations in molecular biophysics with a historical perspective

Kukushkin

Jalkanen

2009

Theor Chem Acc

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We discuss how the basic principles of quantum chemistry and quantum mechanics can be and have been applied to a variety of problems in molecular biophysics. First, the historical development of quantum concepts in biophysics is discussed. Next, we describe a series of interesting applications of quantum chemical methods for studying biologically active molecules, molecular structures and some of the important processes which play a role in living organisms. We discuss the application of quantum chemistry to such processes as energy storage and transformation, and the transmission of genetic information. Quantum chemical approaches are essential to comprehend and understand the molecular nature of these processes. To conclude our work, we present a short discussion of the perspectives of quantum chemical methods in modern biophysics, the field of experimental and theoretical chiral vibrational and electronic spectroscopy.

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“…In such a case the use of a quasi-complete configuration interaction is suggested 63 . When the introduction of a orbitals is necessary the use of the Dei Re 64 procedure which may be considered as a simplification of the LCVO method Ieads to satisfactory results 65 . In many cases the extended Hückel method agrees 66 with a superposition of n orbitals calculated following standatd Hückel procedure and of er orbitals resulting from Dei Re procedure.…”

Section: The Role Of Electronic Computersmentioning

confidence: 99%

Relation between electronic structure and chemical reactivity of organic molecules

Daudel¹

1970

Pure and Applied Chemistry

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This paper gives a brief history of the establishment of relations between electronic structure and chemical reactivity of molecules obtained by using quantum mechanical techniques. After a short introduction devoted to the qualitative period a more important part of the paper is concerned with the discussion of the methods which permit some estimations of the constant rates. Both static and dynamic indices are described. The effect of the solvent is taken into account. Various applications are given showing how it has become possible to predict theoretically new kinds of reactivity or even of reactions which have been really discovered later. The role of electronic computers is stressed. It is stated that quantum chemistry will become more and more important in the near future in the field of biochemistry, chemical industries andin particular pharmacology. THE QUALITATIVE PERIOD'THE study of the structure of molecules was originally carried on by chemists using methods of investigation which were essentially chemical in nature, relating to the chemical composition of substances', 'the nature of the chemical reactions in which a substance takes partF ollowing the discovery of the electron many attempts were made to build an electronic theory of the chemical bond and the farnaus paper of Lewis 2 remains the basis of modern theories relating structure and chemical reactivity. As is well known, another important concept, that of resonance, also had an important role in the development of the theory. Two different groups of organic chemists were responsible for the first important step in that direction. On the one hand, Arndt 3 and collaborators developed the theory of intermediate stages. On the other hand, Robinson 4 and Ingold 5 built the theory of mesomerism. 'The significant feature which these theories had in common was that they considered it possible for the true state of a molecule nottobe identical with that represented by any single classical valence bond structure, but to be intermediate between those represented by two or more different valence bond structures 6 '.

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812. A simple MO–LCAO method for the calculation of charge distributions in saturated organic molecules

Cited by 357 publications

References 0 publications

Pattern Recognition Analysis of a Set of Mutagenic Aliphatic N-Nitrosamines

Pattern Recognition Analysis of a Set of Mutagenic Aliphatic N-Nitrosamines

Role of quantum chemical calculations in molecular biophysics with a historical perspective

Relation between electronic structure and chemical reactivity of organic molecules

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