Graphical Contents
There are not many people in the modern scientific world
that have substantially contributed to several branches of
chemical research, such as quantum chemistry, artificial
intelligence and chemometrics, materials- and structure
characterization and pharmaceutical active ingredients.
The scientific research of academician professor doctor
Du{an Had`i has been scientifically highly productive and
his discoveries undoubtedly represent such an achieve-
ment.
His scientific career has been long, rich, and extensive,
ranging from theoretical studies and explanations of hy-
drogen bond, through the establishment of laboratories
with modern instruments and employing top researchers,
to the practical solutions for human health welfare and en-
vironmental benefits.
He was born on August 26, 1921 in Ljubljana. He ob-
tained his B. Sc. degree from the Chemistry Section of the
Faculty of Philosophy and received his Ph. D. from the
Faculty of Natural and Mathematical Sciences at the
University of Ljubljana.
After his employment in 1948 at the Institute of Che-
mistry of the Slovenian Academy of Sciences and Art his
first research task were the explanation of structure and
properties of coals and the theoretical explanation of coke
formation from young coals containing high levels of
sulpfur. It was at that time that infrared spectroscopy be-
gun to emerge as one of the most important techniques for
the study of macromolecular structures. Professor Maks
Samec, then the director of already independent Institute
of Chemistry, realized the need for acquiring new ideas
and knowledge from already established sources in order
to successfully introduce new modern research tech-
niques. Following this suggestion, Professor Had`i went
to the University of Cambridge, England, for a period
from 1950–1951 to further specialize in the field of in-
frared spectroscopy. After earning his Ph. D. in 1953 he
managed to introduce the first infrared spectrometer in
Ljubljana that opened the way for the continuation of the-
oretical research of the studies of hydrogen bonds in or-
ganic molecules, with an emphasis on short hydrogen
bonds in OH groups. Professor Had`i published a classifi-
cation related to this field that has become one of the most
cited in the world and has been in use ever since.
The ideas of the nature of hydrogen bond spread through-
out the scientific world. The research continued by the use
of a variety of other techniques as X-ray diffraction, in-
elastic neutron scattering, incoherent inelastic neutron
scattering, far infrared spectroscopy, Raman spectroscopy,
nuclear magnetic resonance and quadrupole nuclear mag-
netic resonance. These techniques had slowly established
themselves in Slovenian research area and, by a substan-
tial engagement of Professor Had`i, enabled more de-
tailed structure investigations and also became research
tools for highly-specialized researchers.
Professor Du{an Had`i 
– 90 years old
Memorial Issue
ActaChimicaSlovenica
Graphical Contents
As a natural consequence of using different investigative
techniques there emerged an idea on the possible use of
artificial intelligence in chemical research. The applica-
tion of these ideas has through the years evolved into in-
dependent chemometric investigations.
A new challenge in the scientific career of Professor
Had`i was the development of quantum methods for the
study of medium-size molecules and the role of hydrogen
bonds in biological processes. The main areas studied
were the mechanisms of enzyme reactions and molecular
recognition. The important reactions studied were proton
transfer and hydrogen bond orientation.
By the end of 1980s Professor Had`i initiated and started
the investigations in the field of peptide-based active in-
gredients. The research included specialists from Lek
Pharmaceutical Company, Faculty of Pharmacy, Institute
of Immunology and Microbiology and Ru|er Bo{kovi~
Institute from Zagreb, Croatia. The research was of great
importance to the pharmaceutical industry and was fo-
cused on interaction of active ingredients or appropriate
model molecules with phospholipids. He solved several
challenging problems by the ingenious use of infrared
spectroscopy and model calculations.
Lately, there had emerged a renewed interest in the role of
strong hydrogen bonds in the energetics of enzyme reac-
tions and Professor Had`i returned once again to the stud-
ies of this topic. With the fruitful collaboration of numer-
ous partners from Europe and the U. S. A. he decided on
quantum characterization method. He succeeded in de-
scribing the proton dynamics and established the correla-
tions among various parameters on the basis of the in-
crease of interaction degree and the changes of proton
center-of-gravity.
The scientific work of Professor Had`i was always pres-
ent in the international scientific arena that he frequently
succeeded in transferring it to the home ground. As early
as 1957 he organized the conference on hydrogen bond,
the first after the World War II, that brought together nu-
merous eminent scientists from the West and East, among
them L. Pauling and G. Pimentel (U.S.A.), J. D. Bernal
and C. A. Coulson (Great Britain), M Eigen (Germany)
and M. A. Volkenstein and N. D. Sokolov (then Soviet
Union). He organized, together with J. Zupan, the 2nd in-
ternational conference on the use of computers in chemi-
cal research and education in 1973. In 1986 he was the or-
ganizer of the 6th international symposium on quantitative
relationships between the structure and activity that was
held in Portoro`, Slovenia. He actively presented his work
and that of his collaborators, mostly as invited lectures, at
international conferences and universities throughout the
world.
He shared his knowledge, scientific creativity and excel-
lence and perseverance in work with his junior colleagues
and assistants which have, as a result, evolved into emi-
nent independent researchers, scientists and educators.
Professor Had`i’s whole scientific career has been mostly
affiliated with the Institute of Chemistry (now National
Institute of Chemistry), where he was also a director. His
contributions also helped the Institute to maintain the sta-
tus of a research institution which, together with top,
young researchers faces the ever-arising new challenges.
He also worked at the Faculty of Natural Sciences and
Technology at the University of Ljubljana and at Lek
Pharmaceutical Company.
In the course of his scientific career of over 60 years,
Professor Had`i published more than 280 original scien-
tific papers and 9 chapters in monographs, authored 4
books and edited the proceedings of three international
congresses. The impact of his works has been reflected in
more than 3.000 citations. He also published several criti-
cal contributions on the position and status of science in
our society as well as other important themes regarding
the civil society.
He was the president of the Slovenian Chemical Society
from 1974 to 1986 and currently acts as the Society’s Ho-
norary President. He also performed numerous important
duties in the research authorities of the Republic of Slove-
nia.
Professor Had`i received numerous decorations, awards
and commendations for his highly praised scientific work
from the State and from professional societies. He has
been a regular member of the Slovenian Academy of
Sciences and Arts and an external or corresponding mem-
ber of several foreign Academies. He also received an
honorary doctorate from the University of Uppsala, Swe-
den. He has been an honorary member of many profes-
sional associations and societies.
On the occasion of Professor Had`i’s important anniver-
sary, we all wish him good health, continuing optimistic
spirit and further success with studying hydrogen bonds.
All the best!
Ven~eslav Kau~i~
President, Slovenian Chemical Society