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The book deals with recent scientific highlights on molecular magnetism in Europe. Molecular magnetism is a new interdisciplinary discipline gathering together chemists and physicists, theoreticians and experimentalists. The book intends to provide the reader with documented answers to some current questions. How chemists can use soft conditions to transform molecules in light and transparent magnets? How a molecular system can behave as a single molecule magnet? How to combine several functions in the same molecular system? How light can be used to switch molecular magnetic properties? How can molecules be used for ultimate high density information storage or in quantum computing? What kind of methods do physicists develop and use to explore these new properties of matter? What kind of concepts and calculations can be provided for theoreticians to design new objects and to better understand the field and to enlarge its exciting developments?
The theoretical basis of this book is developed ab ovo. This requires dealing with several problems arising in physical chemistry including the concept of entropy as a thermodynamic coordinate and its relation to probability. Thus Maxwell Boltzmann and Gibbs statistical thermodynamics, and quantum statistics are made considerable use of. A statistical mechanical derivation of the law of mass action for gases and solids is presented, and the problems arising in the application of the law of mass action to the liquid state are addressed. Molecular interactions and how to take them into account when deriving the law of mass action is discussed in some detail sketching a way alternativ to the use of activities. Finally, attention is drawn to the statistical mechanical background to Linear Free Energy Relationships (LFER's) and of Isokinetic Relationships (IKR's) and their connections with molecular interactions.
Metal ions in the brain are a necessity as well as a poison. The
presence of metal ions in the active sites of biological catalysts
or metalloproteins and in the biological functioning of nucleic
acids is very well documented and they are required for brain
activity. On the other hand, metals are very effective in
generating oxidative stress. This effect does not only play a role
in immunology but also is the root of practically all
neurodegenerative disorders by inducing disease via the death of
neurons. Managing metal ions in the brain could therefore be an
important strategy in the search for therapeutic agents used in the
treatment of neurodegenerative diseases. This new title gives an
overview to key topics in the area of metal ions in the brain. It
focuses on the role of metal ions in neurological systems by
describing their advantageous functions as well as their poisonous
features. It is therefore of interest for scientists in
biochemistry and biophysics, physiology, toxicology as well as for
physicians focused on this topic.
'Why are atoms so small?' asks 'naive physicist' in Erwin
Schrodinger's book 'What is Life? The Physical Aspect of the Living
Cell'. 'The question is wrong' answers the author, 'the actual
problem is why we are built of such an enormous number of these
particles'. The idea that everything is built of atoms is quite an
old one. It seems that l Democritus himself borrowed it from some
obscure Phoenician source . The arguments for the existence of
small indivisible units of matter were quite simple. 2 According to
Lucretius observable matter would disappear by 'wear and tear' (the
world exists for a sufficiently long, if not infinitely long time)
unless there are some units which cannot be further split into
parts. th However, in the middle of the 19 century any reference to
the atomic structure of matter was considered among European
physicists as a sign of extremely bad taste and provinciality. The
hypothesis of the ancient Greeks (for Lucretius had translated
Epicurean philosophy into Latin hexameters) was at that time seen
as bringing nothing positive to exact science. The properties of
gaseous, liquid and solid bodies, as well as the behaviour of heat
and energy, were successfully described by the rapidly developing
science of thermodynamics.
Most organic molecules retain their integrity when dissolved, and
even though in such cases the effects exerted by solvents are, in
the language of the coordination chemist, of the "outer sphere"
kind, the choice of solvent can be critical to the successful
outcome of an operation or preparation. Solubilities of reactants
and products must be taken into account, and even if the organic
principals in the reactions retain their integrity, many of the
reagents are electrolytes, and their state of aggregation will
affect their reactivity. In testifying to the importance of
understanding solute-solvent interactions I draw attention to a
large class of inorganic species for which the involvement in the
chemical and physical properties by the solvent is even more deeply
seated. It is comprised by the large body of metal atoms in low
oxidation states for which solvent molecules intervene as reagents.
At the same time, because the ions carry charges, the effects
arising from outer sphere interactions are usually greater than
they are for neutral molecules. To cite an example: when FeCb(s) is
dissolved in water to form a dilute - say O. OlO- solution there is
a complete reorganization of the coordination sphere of the cation.
Whereas in the solid each cation is surrounded by six chloride
ions, in the solution the dominant form is [Fe(H20)6]3+ followed by
[Fe(H20)sCI]2+, [Fe(H20)4CI2]+, etc. in rapidly decreasing
abundance.
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