Special Topic Issue on the Theme
of Nanostructured Systems
This issue of Pure Appl. Chem. is devoted to
papers based upon invited lectures delivered at the first IUPAC-sponsored
Workshop on Advanced Material, "WAM1:
Nanostructured Systems", held at the Hong Kong University for
Science and Technology (HKUST) on July 14-18, 1999.
Why nanostructured material? Chemists contribute to the well-being
of society by exploiting the properties of the elements of the periodic
table, or various forms of combination of elements, to make materials
that are useful for "better living through chemistry." What happens
if we use all the possible combinations that can be made? There remain
great demands for developing new materials to improve our lives in
fields such as medicine, energy, improving the environment, communication
and transportation. Thus, we have to think of new ways to make materials
that can be expected to display properties appropriate to the technologies
of the new Millennium!
The difference in properties of different elements and
their derived compounds is a result of differences in the type of
motion that their electrons can execute. This, in turn, depends on
the space available for the electronic motion and the degree of its
confinement. Thus, the difference between a metal, a semiconductor
and an insulator is attributable to the electrons being delocalized
in the first, more confined in the second and highly confined in the
last. Can we physically cut material size sufficiently to change its
electronic degree of confinement and thus its properties? We do know
that while copper metal is a conductor, the copper atom and small
molecular clusters of copper atoms are insulators. What is the size
of an elemental assembly of a metal (i.e. the number of atoms in it)
at which the metal-semiconductor or the metal-insulator transition
occurs? Of course it depends on the length scale of the property measured.
For semiconductors and metals, a large change in properties, e.g.
absorption, emission, and conductivity, occurs on the nanometer length
scale. Equally important, the property becomes very sensitive to the
size of the nanoparticle. It can thus be expected that many variations
in these properties should be observed for the same material by simply
changing its size. The potential for harnessing these changes of properties
in new technological applications is largely responsible for the current
appeal of this exciting field. These considerations, along with our
personal research interests, convinced me and Professor Joshua Jortner
that it would be opportune to adopt this theme for the first IUPAC
Workshop on Advanced Material.
The publication of the talks given at the Workshop is
timely, given the extraordinary rapidity with which new developments
are taking place in the field. This collection of papers complements
other recent publications of reviews on the topic of nanostructures,
since it is more in the nature of a symposium-in-print and offers
an assembly of short overviews and research papers which capture the
dynamic associated with research at interdisciplinary interfaces,
and with the development of attendant synthetic and analytical techniques.
The promise of unimagined properties of nanostructured materials and
of new-generation applications is an ongoing stimulus for further
research, and it is hoped that this publication will contribute to
the process, and furnish practitioners with new insights and inspiration.
This is truly a multidisciplinary and future-targeted area of scientific
research, and one which fully meets the IUPAC vision of 'new directions
in chemistry', with its promise of hitherto undefined vistas of opportunity
for discovery and exploitation.
The quality of the scientific presentations at this meeting was very
high indeed. The strong international representation is in keeping
with the spirit of IUPAC as well as the global nature of scientific
research. The idea of the meeting was to get scientists active in
advanced material from the West to interact strongly with those from
the Orient. In this regard, we have succeeded as we achieved representation
from seven countries from each side [China (Mainland and Hong Kong),
Japan, Korea, Philippines, Singapore, and Taiwan from the Orient,
and Canada, France, Germany, Israel, Spain, United Kingdom, and USA
from the West]. This great accomplishment of getting us all together
in such a delightful atmosphere was the result of the wise sponsorship
of IUPAC and the great efforts of many people, whom I would like to
IUPAC: for its wisdom to sponsor workshops in
frontier areas of chemical research. We thank the then-IUPAC President,
Prof. Joshua Jortner for cochairing the Workshop. We also thank the
IUPAC Secretariat, in particular its Executive Director, Dr. John
Jost, for his continuous and prompt support and Dr. Fabienne Meyers
for creating and editing our web page for the Workshop and for her
essential assistance in the production of this special volume.
HKUST: for hosting us. We thank Dr. Nai-Teng
Yu of the Chemistry Department, whose willingness to help us by accommodating
the Workshop in his Department was essential; Dr. Shihe Yang whose
continuous hard work and efforts made it possible to follow up the
registration process; the local organizers, in particular, Prof. Leroy
Chang and Ping Sheng, who supplied us with the list of participants,
the names of some invited speakers and the program of a similar meeting
held there recently and the Departmental staff, for their help in
getting the arrangements of this workshop finalized.
Georgia Tech: Dr. Clemens Burda helped in getting
the workshop abstracts and putting the workshop material together,
Ms. Michele Papsidero, my own secretary, spent many hours of hard
work in following the process, from completing the registration list,
to reminding contributors to meet different deadlines including sending
the abstracts, and finally in typing and collating the whole program
for the Workshop. The assistance of the USA Organizing Committee and
in particular, Profs. John Zhang and Rob Whetten at Georgia Tech,
was extremely useful in finalizing the scientific program.
The speakers: I thank both the plenary and invited
speakers who accepted our invitation, most without asking for financial
support. Without them, we would not have had such an excellent scientific
meeting or this valuable volume of Pure Appl. Chem.
I wish to thank Professor James
Bull, the editor of this special issue, for his hard work in making
sure he received the manuscripts in time, for the review process of
these manuscripts and for putting the whole volume together.
Chairman, Organizing Committee
Julius Brown Professor School of Chemistry and Biochemistry Georgia
Institute of Technology