Aromaticity

Aromaticity
Author: Israel Fernandez
Publsiher: Elsevier
Total Pages: 516
Release: 2021-05-16
ISBN 10: 0128227435
ISBN 13: 9780128227435
Language: EN, FR, DE, ES & NL

Aromaticity Book Review:

Evaluating the aromaticity of a molecular system and the influence of this concept on its properties is a crucial step in the development of novel aromatic systems. Modern computational methods can provide researchers with a high level of insight into such aromaticity, but identifying the most appropriate method for assessing a specific system can prove difficult. Aromaticity: Modern Computational Methods and Applications reviews the latest state-of-the-art computational methods in this field and discusses their applicability for evaluating the aromaticity of a system. In addition to covering aromaticity for typical organic molecules, this volume also explores systems possessing transition metals in their structures, macrocycles and even transition structures. The influence of the aromaticity on the properties of these species (including the structure, magnetic properties and reactivity) is highlighted, along with potential applications in fields including materials science and medicinal chemistry. Finally, the controversial and fuzzy nature of aromaticity as a concept is discussed, providing the basis for an updated and more comprehensive definition of this concept. Drawing on the knowledge of an international team of experts, Aromaticity: Modern Computational Methods and Applications is a unique guide for anyone researching, studying or applying principles of aromaticity in their work, from computational and organic chemists to pharmaceutical and materials scientists. Reviews a range of computational methods to assess the aromatic nature of different compounds, helping readers select the most useful tool for the system they are studying Presents a complete guide to the key concepts and fundamental principles of aromaticity Provides guidance on identifying which variables should be modified to tune the properties of an aromatic system for different potential applications

Aromatic character and aromaticity

Aromatic character and aromaticity
Author: Anonim
Publsiher: CUP Archive
Total Pages: 135
Release: 2022
ISBN 10: 1928374650XXX
ISBN 13: 9182736450XXX
Language: EN, FR, DE, ES & NL

Aromatic character and aromaticity Book Review:

Aromaticity

Aromaticity
Author: Peter J. Garratt
Publsiher: Wiley-Interscience
Total Pages: 313
Release: 1986-04-25
ISBN 10: 1928374650XXX
ISBN 13: UOM:39015016100581
Language: EN, FR, DE, ES & NL

Aromaticity Book Review:

Examines aromaticity through the historical and conceptual framework of simple molecular orbital theory. This approach is unique in that theoretical considerations are integrated with experimental observations. The criteria for aromatic, antiaromatic and nonaromatic compounds are discussed in with reference to benzene, cyclobutadiene and cyclooctatetraene. Also includes a chapter on the likely classes of aromatic compounds.

Aromaticity and Antiaromaticity

Aromaticity and Antiaromaticity
Author: Miquel Solà,Alexander I. Boldyrev,Michal K. Cyrañski,T. Marek Krygowski,Gabriel Merino
Publsiher: Wiley
Total Pages: 352
Release: 2021-02-08
ISBN 10: 9781119085898
ISBN 13: 1119085896
Language: EN, FR, DE, ES & NL

Aromaticity and Antiaromaticity Book Review:

A comprehensive review of the essential characteristics and properties of aromaticity, written by leaders of the field Aromaticity and Antiaromaticity: Concepts and Applications offers an authoritative guide that examines the geometrical, electronic, magnetic, thermodynamic characteristics and reactivity properties of aromaticity and provides insight into its nature. Whilst the concept of aromaticity has been known for nearly two centuries, there was no way to accurately measure it nor a theoretical formula to calculate it. The book offers a detailed review of the evolution of aromaticity, from benzene to atomic clusters. The authors, noted experts in the field, explore the new global criteria used to evaluate aromaticity, including the Nucleus Independent Chemical Shift (NICS) index and the electronic indices based on electronic properties. They discuss the inorganic aromatic compounds developed in this century, which induce new concepts like multifold aromaticity. This volume also includes information on the three-dimensional aromaticity found in fullerenes and nanotubes, excited state aromaticity, and the Möbius aromaticity present in some annulenes. This important resource: Contains a comprehensive review of all important aspects of aromaticity, including characteristics, evaluation indexes, reactivity, structural models and three-dimensional aromaticity Offers a review of the evolution of aromaticity, from benzene to atomic clusters Reviews the most recent developments in the field Presents information from leading experts who have made valuable advances in the theoretical understanding of aromaticity Written for graduate students, researchers and academics specializing in aromaticity, organometallic chemistry and computational chemistry, Aromaticity and Antiaromaticity: Concepts and Applications is the most authoritative guide to the characteristics and latest advances in the fields.

Aromaticity in Heterocyclic Compounds

Aromaticity in Heterocyclic Compounds
Author: Tadeusz Marek Krygowski,Michal Ksawery Cyranski
Publsiher: Springer Science & Business Media
Total Pages: 344
Release: 2009-01-30
ISBN 10: 3540683291
ISBN 13: 9783540683292
Language: EN, FR, DE, ES & NL

Aromaticity in Heterocyclic Compounds Book Review:

Heterocyclic chemistry is the biggest branch of chemistry covering two-thirds of the chemical literature. Aromaticity in Heterocyclic Compounds covers hot topics of frontier research summarized by reputed scientists in the field.

Aromaticity and Metal Clusters

Aromaticity and Metal Clusters
Author: Pratim Kumar Chattaraj
Publsiher: CRC Press
Total Pages: 466
Release: 2010-10-15
ISBN 10: 9781439813355
ISBN 13: 1439813353
Language: EN, FR, DE, ES & NL

Aromaticity and Metal Clusters Book Review:

Metal clusters, an intermediate state between molecules and the extended solid, show peculiar bonding and reactivity patterns. Their significance is critical to many areas, including air pollution, interstellar matter, clay minerals, photography, catalysis, quantum dots, and virus crystals. In Aromaticity and Metal Clusters, dozens of international experts explore not only the basic aspects of aromaticity, but also the structures, properties, reactivity, stability, and other consequences of the aromaticity of a variety of metal clusters. Although the concept of aromaticity has been known for nearly two centuries, there is no way to measure it experimentally and no theoretical formula to calculate it. In order to gain insight into its exact nature, the authors of this volume examine various indirect characteristics such as geometrical, electronic, magnetic, thermodynamic, and reactivity considerations. The book begins by discussing the evolution of aromaticity from benzene to atomic clusters. Next, more specialized chapters focus on areas of significant interest. Topics discussed include: Computational studies on molecules with unusual aromaticity Electronic shells and magnetism in small metal clusters A density functional investigation on the structures, energetics, and properties of sodium clusters through electrostatic guidelines and molecular tailoring The correlation between electron delocalization and ring currents in all metallic aromatic compounds Phenomenological shell model and aromaticity in metal clusters Rationalizing the aromaticity indexes used to describe the aromatic behavior of metal clusters 5f orbital successive aromatic and antiaromatic zones in triangular uranium cluster chemistry This collection of diverse contributions, composed of the work of scientists worldwide, is destined to not only answer puzzling questions about the nature of aromaticity, but also to provoke further inquiry in the minds of researchers.

Facts and Theories of Aromaticity

Facts and Theories of Aromaticity
Author: David Lewis (Ph.D.),David Peters
Publsiher: Unknown
Total Pages: 109
Release: 1975
ISBN 10: 1928374650XXX
ISBN 13: UOM:39015016100615
Language: EN, FR, DE, ES & NL

Facts and Theories of Aromaticity Book Review:

Aromaticity in Bridged Biphenyls Containing Metallic Elements

Aromaticity in Bridged Biphenyls Containing Metallic Elements
Author: James Michael Gaidis
Publsiher: Unknown
Total Pages: 608
Release: 1967
ISBN 10: 1928374650XXX
ISBN 13: WISC:89010883924
Language: EN, FR, DE, ES & NL

Aromaticity in Bridged Biphenyls Containing Metallic Elements Book Review:

Aromaticity and Antiaromaticity

Aromaticity and Antiaromaticity
Author: Vladimir I. Minkin,Mikhail N. Glukhovtsev,Boris Ya. Simkin,Boris I︠A︡kovlevich Simkin
Publsiher: Wiley-Interscience
Total Pages: 313
Release: 1994-04-14
ISBN 10: 1928374650XXX
ISBN 13: MINN:31951D01082273Q
Language: EN, FR, DE, ES & NL

Aromaticity and Antiaromaticity Book Review:

Designed to assist chemists in integrating the results of calculations on molecules and ions into their general body of chemical knowledge. Contains recent contributions from theoretical and computational chemistry to the development of the concept of aromaticity (antiaromaticity) and its expansion into new areas such as organometallic and cluster compounds and three-dimensional structures. Updates the modern status of aromaticity and covers basic principles and experimental applications.

Aromaticity

Aromaticity
Author: Marcos Mandado,María J. González Moa,Ricardo A. Mosquera
Publsiher: Nova Science Pub Incorporated
Total Pages: 72
Release: 2008
ISBN 10: 9781604564082
ISBN 13: 1604564083
Language: EN, FR, DE, ES & NL

Aromaticity Book Review:

Aromaticity is among the most frequently used concepts in the chemical literature. Nevertheless, it has to be stressed that aromaticity is not an observable that could be directly obtained from molecular wave function. So, it remains as a controversial concept and its physical origin is still being debated. This has lead to multiple ways for assessing the aromatic or anti-aromatic character of molecules. Thus, several indices of aromaticity have been proposed throughout the literature. It is well-known that aromaticity is strongly related to the electron delocalisation of the electrons along all the centres of the ring. The introduction of the n-order density matrix, and development of n-centre delocalisation indices (n-DIs), has provided a quantitative tool to measure electron delocalisation within a certain ring. Therefore, n-DIs can be regarded as a promising way to determine the actual role played by electron delocalisation in aromaticity. n-DIs are found to be in line with most of the qualitative trends predicted by the harmonic oscillator model of aromaticity indices, HOMAs, aromaticity indices derived from the Chemical Graph Theory, properties of the ring critical points, and circuit resonance energies. It has to be noticed that the direct comparison of n-DIs computed for rings with a different number of centers does not provide a picture of relative aromatic stabilisation. In fact, aromatic stabilisation does not only depend on the extension of the electron delocalisation over the n centres, but also on the number of centres. n-DIs dependence on the number of centres and electrons in a ring prevents to use their direct comparison as a measure of aromatic stabilisation unless an appropriate scaling is applied. Effective Scaled Electron Delocalisation indices, ESED, have been developed for comparing the total aromaticity of polyaromatic hydrocarbons. n-DIs exhibit very different behaviour for aromatic and antiaromatic hydrocarbons. Thus, an aromatic compound is one whose multicenter electron delocalisation is larger than that of the corresponding linear structure, whereas an antiaromatic compound is one where the multi-centre electron delocalisation is smaller than that of the linear molecule. Those compounds that display very small differences between linear and cyclic structures may be called non-aromatic. n-DIs are also found as a promising tool to study the aromaticity of transition states in concerted processes. This book also reports on its application to the study of the aromaticity in all metal compounds.

Aromaticity Pseudo aromaticity Anti aromaticity

 Aromaticity  Pseudo aromaticity  Anti aromaticity
Author: Ernst David Bergmann,Bernard Pullman
Publsiher: Israel Academy of Sciences and Humanities
Total Pages: 398
Release: 1971
ISBN 10: 1928374650XXX
ISBN 13: STANFORD:36105004123233
Language: EN, FR, DE, ES & NL

Aromaticity Pseudo aromaticity Anti aromaticity Book Review:

Aromatic Character and Aromaticity

Aromatic Character and Aromaticity
Author: G. M. Badger
Publsiher: Cambridge University Press
Total Pages: 144
Release: 1969-01-02
ISBN 10: 9780521095433
ISBN 13: 0521095433
Language: EN, FR, DE, ES & NL

Aromatic Character and Aromaticity Book Review:

Originally published in 1969, this book analyses the special properties of benzene and its derivatives, which give them their distinct aromatic character. The text first discusses the structure of benzene, including the light shed on it by physical methods and wave mechanics, and the structure of polycyclic benzenoid hydrocarbons and heterocyclic aromatic compounds. Aromaticity is defined as a function of the electronic structure of the molecule or ion in question and it is shown that this has important consequences in respect of bond lengths, resonance energies, electronic absorption spectra and induced ring currents. Final chapters discuss how far aromatic character and aromaticity are associated with non-benzenoid hydrocarbons and with more complex systems.

Aromaticity Pseudo aromaticity Anti aromaticity

Aromaticity  Pseudo aromaticity  Anti aromaticity
Author: Anonim
Publsiher: Unknown
Total Pages: 398
Release: 1971
ISBN 10: 1928374650XXX
ISBN 13: OCLC:320401419
Language: EN, FR, DE, ES & NL

Aromaticity Pseudo aromaticity Anti aromaticity Book Review:

Aromaticity

Aromaticity
Author: University of Sheffield,Chemical Society (Great Britain)
Publsiher: Unknown
Total Pages: 249
Release: 1967
ISBN 10: 1928374650XXX
ISBN 13: UOM:39015031045878
Language: EN, FR, DE, ES & NL

Aromaticity Book Review:

Aromaticity Pseudo aromaticity Anti aromaticity

Aromaticity  Pseudo aromaticity  Anti aromaticity
Author: Ernst D. Bergmann
Publsiher: Unknown
Total Pages: 398
Release: 1971
ISBN 10: 1928374650XXX
ISBN 13: OCLC:251168383
Language: EN, FR, DE, ES & NL

Aromaticity Pseudo aromaticity Anti aromaticity Book Review:

Advanced Organic Chemistry

Advanced Organic Chemistry
Author: Francis A. Carey,Richard J. Sundberg
Publsiher: Springer Science & Business Media
Total Pages: 832
Release: 2013-11-11
ISBN 10: 1461397952
ISBN 13: 9781461397953
Language: EN, FR, DE, ES & NL

Advanced Organic Chemistry Book Review:

The purpose of this edition, like that of the earlier ones, is to provide the basis for a deeper understanding of the structures of organic compounds and the mechanisms of organic reactions. The level is aimed at advanced undergraduates and beginning graduate students. Our goals are to solidify the student's understanding of basic concepts provided by an introduction to organic chemistry and to present more information and detail, including quantitative information, than can be presented in the first course in organic chemistry. The first three chapters consider the fundamental topi~s of bonding theory, stereochemistry, and conformation. Chapter 4 discusses the techniques that are used to study and characterize reaction mechanisms. Chapter 9 focuses on aromaticity and the structural basis of aromatic stabilization. The remaining chapters consider basic reaction types, including substituent effects and stereochemistry. As compared to the earlier editions, there has been a modest degree of reorganization. The emergence of free-radical reactions in synthesis has led to the inclusion of certain aspects of free-radical chemistry in Part B. The revised chapter, Chapter 12, empha sizes the distinctive mechanistic and kinetic aspects of free-radical reactions. The synthetic applications will be considered in Part B. We have also split the topics of aromaticity and the reactions of aromatic compounds into two separate chapters, Chapters 9 and 10. This may facilitate use of Chapter 9, which deals with the nature of aromaticity, at an earlier stage if an instructor so desires.

Aromaticity and Other Conjugation Effects

Aromaticity and Other Conjugation Effects
Author: Rolf Gleiter,G. Haberhauer
Publsiher: John Wiley & Sons
Total Pages: 452
Release: 2012-09-24
ISBN 10: 9783527329342
ISBN 13: 352732934X
Language: EN, FR, DE, ES & NL

Aromaticity and Other Conjugation Effects Book Review:

The authors provide an excellent overview of conjugation effects in organic chemistry within and between Pi systems. Besides various aspects of aromaticity one finds detailed discussions of homo-, spiroand hyperconjugation as well as effects of through-space and throughbond interactions. These effects are presented on the basis of experimental results and are analyzed by the use of qualitative arguments of perturbation theory and from a comparison with results from high level ab initio calculations. This book is a must-have for bachelor students from the second year on, master and PhD students of chemistry. Also students in science such as physics, biology and medicine will benefit from the concepts described in the book. Furthermore, chemists in research and development will be grateful to find here an overview of conjugation effects allowing to understand the structures, the dynamics and the reactivity of molecules.

AROMATICITY PSEUDO AROMATICITY ANTI AROMATICITY PROCEEDINGS OF AN INTERNATIONAL SYMPOSIUM 3RD JERUSALEM SYMPOSIUM ON QUANTUM CHEMISTRY AND BIOCHEMISTRY

AROMATICITY PSEUDO AROMATICITY ANTI AROMATICITY  PROCEEDINGS OF AN INTERNATIONAL SYMPOSIUM  3RD JERUSALEM SYMPOSIUM ON QUANTUM CHEMISTRY AND BIOCHEMISTRY
Author: Anonim
Publsiher: Unknown
Total Pages: 135
Release: 2022
ISBN 10: 1928374650XXX
ISBN 13: OCLC:846551017
Language: EN, FR, DE, ES & NL

AROMATICITY PSEUDO AROMATICITY ANTI AROMATICITY PROCEEDINGS OF AN INTERNATIONAL SYMPOSIUM 3RD JERUSALEM SYMPOSIUM ON QUANTUM CHEMISTRY AND BIOCHEMISTRY Book Review:

Benzene and Aromaticity

Benzene and Aromaticity
Author: Muhammad Arifur Rahman
Publsiher: LAP Lambert Academic Publishing
Total Pages: 92
Release: 2012-08
ISBN 10: 9783659207303
ISBN 13: 3659207306
Language: EN, FR, DE, ES & NL

Benzene and Aromaticity Book Review:

The understanding of benzene and hence of all aromatic compounds, proved to be so important for both applied chemistry and Pharmacy. Many important chemical compounds are derived from benzene by replacing one or more of its hydrogen atoms with another functional group. In heterocycles, carbon atoms in the benzene ring are replaced with other elements. In this book the chemical nature of benzene and aromatic reaction describes smoothly.

Quantitative Study on Local Aromaticity

Quantitative Study on Local Aromaticity
Author: Mozhgan Shahamirian
Publsiher: LAP Lambert Academic Publishing
Total Pages: 100
Release: 2012
ISBN 10: 9783659300448
ISBN 13: 3659300446
Language: EN, FR, DE, ES & NL

Quantitative Study on Local Aromaticity Book Review:

Substituent Effect on Local Aromaticity has been studied in series of mono-and di-substituted biheterocycles (quinoline, isoquinoline, quinoxaline, quinazoline, 1H-Indole, 1H-Indazole, 1H- Benzo d]imidazole). Electronically based indices (PDI, ATI and FLU) have been employed to investigate the substituent effect on the -electron delocalization in both heterocycle and benzenoid rings. Three typical substituents (Cl, OCH3 and CN) with different inductive and resonance effect have been selected. Generally, substituent causes a reduction in aromaticity irrespective of whether it is electron attracting or electron donating. Moreover, it is found that the substituent situation with respect to the heteroatom has a significant influence on the aromaticity, and irrespective of whether the two substituents form a meta or para isomer, they preferably choose the position which leads to the maximum aromaticity character. Also, influence of increasing the number of N as heteroatom and their sequences on -electron delocalization of aza derivatives of naphthalene and indole have been investigated by use of different quantitative descriptors including HOMA, NICS and electronic indices.