Page 30 - Strategies and Applications in Quantum Chemistry From Molecular Astrophysics to Molecular Engineer

QUANTUM CHEMISTRY: THE NEW FRONTIERS 15

experiments [30]. The future activity of group IV will be the forefront for further attempts
to amend and to extend the quantum theory.

5. Conclusions
My attempt of depicting the new frontiers for Quantum Chemistry has no produced
exhaustive and detailed indications. It is almost impossible to present in a few pages
indications of this type, of questionable validity even if expressed as final report of a panel
of experts, after a hard collective work on this theme. Quantum Chemistry is in fact one of
the cornerstones of Chemistry, enjoying good health as the other branches of Chemistry,
and there are ample and varied perspectives of progress. A selection of some themes would
means to indulge too much to personal tastes.
I have tried to sketch a partition of the various approaches in Quantum Chemistry into four
groups. This taxonomy is open to criticism and does not imply, in my intention, an
exclusive assignation of each quantum chemist to one of the four groups.
The main message of this short undertaking is that Quantum Chemistry in the different
facets it displays, still is an unique discipline, and the activities of a single researcher may
be often assigned to different groups.

Quantum Chemistry is a mature discipline: the roots are very far in the past, and during his
life, more than sixty years, it has been the subject of a "scientific revolution", and a second
important change (or "revolution") is on the verge. This change will perhaps modify the
relative importance of the various approaches, which I have denoted as groups, and surely
will present new challenges to the discipline. Some details and some suggestions have
been given in the preceding pages; here I limit myself to few conclusive remarks.
Molecular quantum chemistry in its computational version has to merge in a more intimate
and effective way with other branches of quantum mechanics and other disciplines or
techniques. The main lines of future evolution will be done by the adoption of complex
strategies involving several techniques, the molecular quantum chemistry, which embodies
the basic understanding of molecular structures and properties, quantum statistics, at the
equilibrium and out of the equilibrium, and many ancillary techniques, from information
theory to computer graphics, etc. The dynamic methods, and all the aspects involving time,
should make more efficient, the temperature should have a better defined status in the
theory.

A period of re-formulation of the theory, similar under some aspects to that which has
characterized quantum chemistry in the years 1930-1960, but projected toward more
complex objectives, should be opened now.
One of the main avenues open to quantum chemistry is that of the complex, very complex,
systems. There are the basic premise to reach these goals. I end thus this overview with a
note of optimism.

References
1. I. Lakatos and I. Musgrave "Criticism and the Growth of Knowledge" , Cambridge
Univ. Press, London (1970).