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The third and last volume of this treatise IS concerned with
important applications of the quantum~theory of chemical reactions
to chemisorption, catalysis and biochemical reactions. The book
begins with an important paper devoted to the theoretical
background of heterogeneous catalysis. It is followed by two papers
showing typical applications of wave mechanics to the analysis of
chemisorption. Catalysed gas-solid reactions are chosen to
illustrate gas, organic solid state reaction and some aspects of
the mechanism of the FISCHER-TROPSCH synthesis are presented. The
second part of the book is devoted to biochemical applications of
quantum chemistry. Two papers are concerned with the quantum theory
of enzyme activity. Two others present recent progress of quantum
pharmacology. Finally an important contribution to the theory of
intermolecular forces is made in the view of possible applications
to biochemical problems. vii R. Daudel, A. Pullman, L. Salem, and
A. Viellard reds.), Quantum Theory o/Chemical Reactions, Volume
III, vii. Copyright (c) 1982 by D. Reidel Publishing Company.
THEORETICAL BACKGROUND OF HETEROGENEOUS CATALYSIS J.E.Germain
Laboratoire de Catalyse Appliquee et Cinetique Heterogene L. A. 231
du Centre National de la Recherche Scientifique Universite Claude
Bernard Lyon I, E.S.C.I.L. 43 Boulevard du 11 Novembre 1918, 69622
Villeurbanne Cedex. Heterogeneous Catalysis is a surface Kinetic
phenomenon by which a chemical reaction between molecules of a
fluid phase is accelerated (activity) and oriented (selectivity) by
contact with a solid phase (catalysts, without change of the solid.
The second volume of this treatise lS concerned with three
important problems: a) environmental effects b) reaction mechanisms
c) photochemical processes An important paper is devoted to the
solvation problem. The local field representation of surrounding
medium effect is analyzed and an application is made to the study
of ambident reaction. A paper is devoted to the study of chemical
reactivity in inert matrices and a theory of the effect of rare gas
matrices on molecules is presented. Six papers are concerned with
chemical reactions mechanisms. They are related to migration
reactions, nucleophilic additions and electrophilic additions, and
homogeneous catalytic reactions. Finally, some aspects of the
photochemical processes are discussed. The evolution of
electronically excited molecules is analyzed and the natural
correlation method is presented. The role of Rydberg states' is
photochemistry is suggested, we believe, for the first time. The
sudden polarization in olefins is described in a critical way and a
new phenomenon is presented: the pho tochemical attachment of
aliphatic hydrocarbons to polynuclear aromatic hydrocarbons. vii R.
Daudel, A. Pullman, L. Salem, and A. Veillard (eds.;, Quantum
Theory of Chemical Reactions, Volume II, vii. Copyright (c) 1980 by
D. Reidel Publishing Company. THE SUPERMOLECULE APPROACH TO THE
SOLVATION PROBLEM A. PULLMAN Institut de BioLogie Physico-Chimique
Laboratoire de Biochimie Theorique, associe au C.N.R.S."
This treatise is devoted to an analysis of the present state of the
quantum theory of chemical reactions. It will be divided into three
volumes and will contain the contributions to an international
seminar organized by the editors. The first one, is concerned with
the fundamental problems which occur when studying a gas phase
reaction or a reaction for which the solvent effect is not taken
into account. The two first papers show how the collision theory
can be used to predict the behaviour of interacting small
molecules. For large molecules the complete calculations are not
possible. We can only estimate the reaction path by calculating
important areas of the potential surfaces. Four papers are
concerned with this important pro cess. Furthermore, in one of
these, the electronic reorganization which occurs along the
reaction path is carefully analyzed. ~~o papers are devoted to the
discussion of general rules as aromaticity rules, symmetry rules.
The last two papers are concerned with the electrostatic molecular
poten tial method which is the modern way of using static indices
to establish relations between structure and chemical reactivity.
Volume II will be devoted to a detailed analysis of the role of the
solvent and volume III will present important applications as
reaction mechanisms, photochemistry, catalysis, biochemical
reactions and drug design. SOME RECENT DEVELOPMENTS IN THE
MOLECULAR TREATMENT OF ATOM-ATOM COLLISIONS.
This book contains the transcripts of the lectures presented at the
NATO Advanced study Institute on "Computational Techniques in
Quantum Chemistry and Molecular Physics," held at Ramsau, Germany,
4th - 21st Sept. 1974. Quantum theory was developed in the early
decades of this century and was first applied to problems in
chemistry and molecular physics as early as 1927. It soon emerged
however, that it was impossible to con sider any but the simplest
systems in any quantita tive detail because of the complexity of
Schrodinger's equation which is the basic equation for chemical and
molecular physics applications. This remained the si tuation until
the development, after 1950, of elec tronic digital computers. It
then became possible to attempt approximate solutions of
Schrodinger's equa tion for fairly complicated systems, to yield
results which were sufficiently accurate to make comparison with
experiment meaningful. Starting in the early nineteen sixties in
the United States at a few centres with access to good computers an
enormous amount of work went into the development and
implementation of schemes for approximate solu tions of
Schrodinger's equation, particularly the de velopment of the
Hartree-Fock self-consistent-field scheme. But it was soon found
that the integrals needed for application of the methods to
molecular problems are far from trivial to evaluate and cannot be
easily approximated."
Over the last twenty years, developments of the ab initio metho
dologies and of the computing capacities have progressively turned
quantum chemistry into a predictive tool for molecular systems
involving only light elements. The situation appears less advanced
for systems containing transition metal elements where specific
difficulties arise, like those 1inked to the quasi-degeneracy of
the lowest atomic states. Correlation effects, which are important
only for quantitative accuracy in the treatment of molecules made
of light elements, need sometimes to be considered even for a
qualitative des cription of transition metals systems (like the
multiple metal-metal bond). The treatment of atoms of a high atomic
number has necessited the development of model potential methods.
These difficulties ex acerbate for systems containing several trans
ition atoms a correct description of the dichromium molecule Crz
still represents a challenge to quantum chemists. Yet many advances
have been made recently in the theoretical treatment of these
systems, despite the fact that our understanding still remains
disparate with a variety of models and methodologies used more or
less successfully (one-electron models, explicitly correlated ab
initio methods, density functional formalisms). For these reasons,
a NATO Advanced Research Workshop was organized to review in detail
the state-of-the-art techniques and at the same time the most
common applications. These encompass many fields including the
spectroscopy of diatomics and small aggregates, structure and
reactivity problems in organometallic chemistry, the cluster
surface analogy with its implications for heterogeneous catalysis
and the description of extended structures."
Over the last twenty years, developments of the ab initio metho
dologies and of the computing capacities have progressively turned
quantum chemistry into a predictive tool for molecular systems
involving only light elements. The situation appears less advanced
for systems containing transition metal elements where specific
difficulties arise, like those 1inked to the quasi-degeneracy of
the lowest atomic states. Correlation effects, which are important
only for quantitative accuracy in the treatment of molecules made
of light elements, need sometimes to be considered even for a
qualitative des cription of transition metals systems (like the
multiple metal-metal bond). The treatment of atoms of a high atomic
number has necessited the development of model potential methods.
These difficulties ex acerbate for systems containing several trans
ition atoms a correct description of the dichromium molecule Crz
still represents a challenge to quantum chemists. Yet many advances
have been made recently in the theoretical treatment of these
systems, despite the fact that our understanding still remains
disparate with a variety of models and methodologies used more or
less successfully (one-electron models, explicitly correlated ab
initio methods, density functional formalisms). For these reasons,
a NATO Advanced Research Workshop was organized to review in detail
the state-of-the-art techniques and at the same time the most
common applications. These encompass many fields including the
spectroscopy of diatomics and small aggregates, structure and
reactivity problems in organometallic chemistry, the cluster
surface analogy with its implications for heterogeneous catalysis
and the description of extended structures."
The third and last volume of this treatise IS concerned with
important applications of the quantum~theory of chemical reactions
to chemisorption, catalysis and biochemical reactions. The book
begins with an important paper devoted to the theoretical
background of heterogeneous catalysis. It is followed by two papers
showing typical applications of wave mechanics to the analysis of
chemisorption. Catalysed gas-solid reactions are chosen to
illustrate gas, organic solid state reaction and some aspects of
the mechanism of the FISCHER-TROPSCH synthesis are presented. The
second part of the book is devoted to biochemical applications of
quantum chemistry. Two papers are concerned with the quantum theory
of enzyme activity. Two others present recent progress of quantum
pharmacology. Finally an important contribution to the theory of
intermolecular forces is made in the view of possible applications
to biochemical problems. vii R. Daudel, A. Pullman, L. Salem, and
A. Viellard reds.), Quantum Theory o/Chemical Reactions, Volume
III, vii. Copyright (c) 1982 by D. Reidel Publishing Company.
THEORETICAL BACKGROUND OF HETEROGENEOUS CATALYSIS J.E.Germain
Laboratoire de Catalyse Appliquee et Cinetique Heterogene L. A. 231
du Centre National de la Recherche Scientifique Universite Claude
Bernard Lyon I, E.S.C.I.L. 43 Boulevard du 11 Novembre 1918, 69622
Villeurbanne Cedex. Heterogeneous Catalysis is a surface Kinetic
phenomenon by which a chemical reaction between molecules of a
fluid phase is accelerated (activity) and oriented (selectivity) by
contact with a solid phase (catalysts, without change of the solid.
This book contains the transcripts of the lectures presented at the
NATO Advanced study Institute on "Computational Techniques in
Quantum Chemistry and Molecular Physics," held at Ramsau, Germany,
4th - 21st Sept. 1974. Quantum theory was developed in the early
decades of this century and was first applied to problems in
chemistry and molecular physics as early as 1927. It soon emerged
however, that it was impossible to con sider any but the simplest
systems in any quantita tive detail because of the complexity of
Schrodinger's equation which is the basic equation for chemical and
molecular physics applications. This remained the si tuation until
the development, after 1950, of elec tronic digital computers. It
then became possible to attempt approximate solutions of
Schrodinger's equa tion for fairly complicated systems, to yield
results which were sufficiently accurate to make comparison with
experiment meaningful. Starting in the early nineteen sixties in
the United States at a few centres with access to good computers an
enormous amount of work went into the development and
implementation of schemes for approximate solu tions of
Schrodinger's equation, particularly the de velopment of the
Hartree-Fock self-consistent-field scheme. But it was soon found
that the integrals needed for application of the methods to
molecular problems are far from trivial to evaluate and cannot be
easily approximated."
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