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Gilles Klopman
Gilles Klopman (February 24, 1933 – January 10, 2015) was the Charles F. Mabery Professor of Research in Chemistry, Oncology and Environmental Health Sciences Director of the Laboratory for Decision Support Methodologies at Case Western Reserve University in Cleveland, Ohio, and Adjunct Professor of Environmental and Occupational Health, (University of Pittsburgh) Dr. Klopman was educated in Belgium and the United States in theoretical chemistry, physical organic chemistry (L. es Sc., University of Brussels (Belgium), 1956, Dr. es Sc., University of Brussels, 1960, Postdoctoral Fellow, University of Texas, 1965–66) Structure-Activity Studies of Biologically Active Molecules Professor Klopman’s work has involved the evaluation of chemical reactivity and includes experimental determination of reactivity indices and substituent constants to the development of reactivity theories . He has contributed significantly to the concept of charge and orbital controlled reactions where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Case Western Reserve University
Case Western Reserve University (CWRU) is a private research university in Cleveland, Ohio. Case Western Reserve was established in 1967, when Western Reserve University, founded in 1826 and named for its location in the Connecticut Western Reserve, and Case Institute of Technology, founded in 1880 through the endowment of Leonard Case Jr., formally federated. Case Western Reserve University is a member of the Association of American Universities and is classified among "R1: Doctoral Universities – Very high research activity". According to the National Science Foundation, in 2019 the university had research and development (R&D) expenditures of $439 million, ranking it 20th among private institutions and 58th in the nation. The university has eight schools that offer more than 100 undergraduate programs and about 160 graduate and professional options. Seventeen Nobel laureates have been affiliated with Case Western Reserve's faculty and alumni or one of its two predecessor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleveland, Ohio
Cleveland ( ), officially the City of Cleveland, is a city in the United States, U.S. U.S. state, state of Ohio and the county seat of Cuyahoga County, Ohio, Cuyahoga County. Located in the northeastern part of the state, it is situated along the southern shore of Lake Erie, across the U.S. Canada–United States border, maritime border with Canada, northeast of Cincinnati, northeast of Columbus, Ohio, Columbus, and approximately west of Pennsylvania. The largest city on Lake Erie and one of the major cities of the Great Lakes region, Cleveland ranks as the List of United States cities by population, 54th-largest city in the U.S. with a 2020 population of 372,624. The city anchors both the Greater Cleveland, Greater Cleveland metropolitan statistical area (MSA) and the larger Northeast Ohio, Cleveland–Akron–Canton combined statistical area (CSA). The CSA is the most populous in Ohio and the 17th largest in the country, with a population of 3.63 million in 2020, while th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Pittsburgh
The University of Pittsburgh (Pitt) is a public state-related research university in Pittsburgh, Pennsylvania. The university is composed of 17 undergraduate and graduate schools and colleges at its urban Pittsburgh campus, home to the university's central administration and around 28,000 undergraduate and graduate students. The 132-acre Pittsburgh campus includes various historic buildings that are part of the Schenley Farms Historic District, most notably its 42-story Gothic revival centerpiece, the Cathedral of Learning. Pitt is a member of the Association of American Universities and is classified among "R1: Doctoral Universities – Very high research activity". It is the second-largest non-government employer in the Pittsburgh metropolitan area. Pitt traces its roots to the Pittsburgh Academy founded by Hugh Henry Brackenridge in 1787. While the city was still on the edge of the American frontier at the time, Pittsburgh's rapid growth meant that a proper university ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theoretical Chemistry
Theoretical chemistry is the branch of chemistry which develops theoretical generalizations that are part of the theoretical arsenal of modern chemistry: for example, the concepts of chemical bonding, chemical reaction, valence, the surface of potential energy, molecular orbitals, orbital interactions, and molecule activation. Overview Theoretical chemistry unites principles and concepts common to all branches of chemistry. Within the framework of theoretical chemistry, there is a systematization of chemical laws, principles and rules, their refinement and detailing, the construction of a hierarchy. The central place in theoretical chemistry is occupied by the doctrine of the interconnection of the structure and properties of molecular systems. It uses mathematical and physical methods to explain the structures and dynamics of chemical systems and to correlate, understand, and predict their thermodynamic and kinetic properties. In the most general sense, it is explanation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Organic Chemistry
Physical organic chemistry, a term coined by Louis Hammett in 1940, refers to a discipline of organic chemistry that focuses on the relationship between chemical structures and reactivity, in particular, applying experimental tools of physical chemistry to the study of organic molecules. Specific focal points of study include the rates of organic reactions, the relative chemical stabilities of the starting materials, reactive intermediates, transition states, and products of chemical reactions, and non-covalent aspects of solvation and molecular interactions that influence chemical reactivity. Such studies provide theoretical and practical frameworks to understand how changes in structure in solution or solid-state contexts impact reaction mechanism and rate for each organic reaction of interest. Application Physical organic chemists use theoretical and experimental approaches work to understand these foundational problems in organic chemistry, including classical and st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-empirical Quantum Chemistry Methods
Semi-empirical quantum chemistry methods are based on the Hartree–Fock formalism, but make many approximations and obtain some parameters from empirical data. They are very important in computational chemistry for treating large molecules where the full Hartree–Fock method without the approximations is too expensive. The use of empirical parameters appears to allow some inclusion of electron correlation effects into the methods. Within the framework of Hartree–Fock calculations, some pieces of information (such as two-electron integrals) are sometimes approximated or completely omitted. In order to correct for this loss, semi-empirical methods are parametrized, that is their results are fitted by a set of parameters, normally in such a way as to produce results that best agree with experimental data, but sometimes to agree with ''ab initio'' results. Type of simplifications used Semi-empirical methods follow what are often called empirical methods where the two-electron p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MINDO
MINDO, or Modified Intermediate Neglect of Differential Overlap is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Intermediate Neglect of Differential Overlap ( INDO) method of John Pople. It was developed by the group of Michael Dewar and was the original method in the MOPAC program. The method should actually be referred to as MINDO/3. It was later replaced by the MNDO MNDO, or Modified Neglect of Diatomic Overlap is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Neglect of Diatomic Differential Overlap integral approximation ... method, which in turn was replaced by the PM3 and AM1 methods. References * Semiempirical quantum chemistry methods {{quantum-chemistry-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klopman-Salem Equation
In the theory of chemical reactivity, the Klopman-Salem equation describes the energetic change that occurs when two species approach each other in the course of a reaction and begin to interact, as their associated molecular orbitals begin to overlap with each other and atoms bearing partial charges begin to experience attractive or repulsive electrostatic forces. First described independently by Gilles Klopman and Lionel Salem in 1968, this relationship provides a mathematical basis for the key assumptions of frontier molecular orbital theory In chemistry, frontier molecular orbital theory is an application of MO theory describing HOMO/LUMO interactions. History In 1952, Kenichi Fukui published a paper in the ''Journal of Chemical Physics'' titled "A molecular theory of reactivity ... (i.e., theory of HOMO-LUMO interactions) and hard soft acid base (HSAB) theory. Conceptually, it highlights the importance of considering both electrostatic interactions and orbital intera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theoretical Chemists
A theory is a rational type of abstract thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking is often associated with such processes as observational study or research. Theories may be scientific, belong to a non-scientific discipline, or no discipline at all. Depending on the context, a theory's assertions might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings. In modern science, the term "theory" refers to scientific theories, a well-confirmed type of explanation of nature, made in a way consistent with the scientific method, and fulfilling the criteria required by modern science. Such theories are described in such a way that scientific tests should be able to provide empirical support for it, or empirical contradiction (" falsify") of it. Scientific theories are the most reliable, rigorous, and com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
21st-century American Chemists
The 1st century was the century spanning AD 1 ( I) through AD 100 ( C) according to the Julian calendar. It is often written as the or to distinguish it from the 1st century BC (or BCE) which preceded it. The 1st century is considered part of the Classical era, epoch, or historical period. The 1st century also saw the appearance of Christianity. During this period, Europe, North Africa and the Near East fell under increasing domination by the Roman Empire, which continued expanding, most notably conquering Britain under the emperor Claudius (AD 43). The reforms introduced by Augustus during his long reign stabilized the empire after the turmoil of the previous century's civil wars. Later in the century the Julio-Claudian dynasty, which had been founded by Augustus, came to an end with the suicide of Nero in AD 68. There followed the famous Year of Four Emperors, a brief period of civil war and instability, which was finally brought to an end by Vespasian, ninth Roman ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2015 Deaths
This is a list of deaths of notable people, organised by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked here. 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 See also * Lists of deaths by day * Deaths by year {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
