Attraction of Each Department

Department of Chemistry

  • Yoshio Umezawa (Professor, Department of Chemistry)

History

Figure 0

Launching a balloon on the Antarctic ice sheet for ozone hole observation

Figure 1

Figure 1: Old building of the Department of Chemistry (presently the East Wing) facing the Gotenshita athletic ground, as viewed from the avenue. This is one of most beautiful spots on the Hong campus.

The Department of Chemistry of the University of Tokyo is one of the oldest departments of the University. In fact, the Department has a longer history than the University itself. The Department originally superseded a school of Western learning founded by the Tokugawa shogunate government. Its first students graduated in 1877, earlier than any other students of the University.

An attractive red brick building facing the second canteen, built 83 years ago, is one of the oldest buildings on the University's Hongo campus. It is preserved as a historical building that remained intact through both the Great Kanto Earthquake and air raids during World War II (Figure 1).

The purpose of chemistry is to study and explore such objects as vast varieties of materials that constitute nature, the magnificent realms of materials and living organisms built upon them. The study of material properties, the study of laws, and the study of chemical reactions among materials are conducted at the molecular or molecular aggregation level. Furthermore, the enhancement of basic understanding in science, the creation or invention of new materials, new methodologies for observation, and analysis of materials based on that basic understanding, depend on such studies. This is particularly true for all the most advanced areas of modern science and technology, including biotechnology, electronics, new materials and high functionality materials. Thus chemistry forms the very basis not only of natural science and engineering but also of a wide variety of areas including medicine, pharmacy, agriculture and environmental science.

There are numerous precedent research achievements of historical importance conducted at the Department of Chemistry. The discovery of rotational isomers by Professor Sanichiro Mizushima is just one example. He discovered that the internal rotation of dichloroethane is not free rotation but involves zigzags due to the presence of restrictions. The discovery was a great achievement because it marked the beginning of a concept that led to understanding of the α-helix and other conformations of molecules. Moreover, it introduced the idea of flexibility of molecular structures along with the discovery of the “wobbliness” of cyclohexane (discovery of the inversed isomers of chair and boat types).

‘Ajinomoto’, now a well-known chemical seasoning, is a constituent of the extract separated from the supernatant of fluid obtained by boiling konbu (seaweed). Professor Kikunae Ikeda directed his attention to the constituent because it seemed to contain the essence of tastiness. He thoroughly studied the constituent in order to find out what kind of chemical substance it was. He successfully identified it as sodium glutamate, a type of amino acid. This discovery led to the patenting of what is known today as ‘Ajinomoto’. The academic significance of this achievement is the introduction into chemistry of the concept of “tastiness” which is based on a specific constituent, an achievement somewhat similar to the discovery of hormones and pheromones.

In the early 1950s, a laboratory team of Professor Hideo Akamatsu discovered that adding iodine to polycyclic aromatic hydrocarbon (compound characterized by two-dimensional chaining of many benzene rings) would dramatically increase electric conductance from the insulator level to the semiconductor level. This was a great achievement of historical significance as the discovery of the “organic semiconductor” and the introduction of its concept. A paper by Akamatsu, Inokuchi and Matsunaga published in Nature in 1954 has been widely read to date. It goes without saying that this achievement established the basis for conductive high polymers in the subsequent period.

More than 3,000 students have graduated from the Department of Chemistry ever since its establishment. Many of them have been in the leading positions in the realm of chemistry studies in Japan, either as researchers and lecturers at universities and governmental institutions, or researchers at industrial research institutions.

Education

With regard to undergraduate education, we emphasize the importance of learning through experiments as our basic policy, as chemistry is an empirical science. Juniors spend the afternoon of all weekdays on experimental exercises. In addition to the experiments, they attend morning lectures. Lectures continue through to the summer term of their final year, and credits are given for attendance at these lectures and lectures on related subjects. Seniors are assigned to laboratories at the start of their academic year. They start conducting research experiments in preparation for their graduation theses. This is supposed to be the most fulfilling time for the students, as they experience for the first time in their university life what it really means to study natural sciences.

After completing their undergraduate study project, most students choose to further continue their studies in the Department of Chemistry or another department to work towards their Master's Degree. The staff involved in research and education programs at the Department of Chemistry include not only its own staff but also members of various other research institutions, including the Research Centre for Spectrochemistry, the Laboratory for Earthquake Chemistry, the Institute for Solid State Physics, the Graduate School of Arts and Sciences, the Ocean Research Institute, the Earthquake Research Institute, and the Japan Aerospace Exploration Agency (JAXA) Institute of Space and Astronautical Science.

Research

The Department of Chemistry has been pursuing a 21st century centers-of-excellence (COE) program since the year 2005 under the title of “Center for Frontier Chemistry Focusing on Molecular Dynamism.” Under this COE program, selected chemistry and material science research organizations in Japan compete for overall excellence as centers of research and education. The Department of Chemistry has been acclaimed as the most outstanding of such organizations in Japan in this area and has won a significant amount of research and education funding from the government of Japan for five consecutive years.

The purpose of our COE research program is to study molecular theories that explore the dynamic nature of molecules, with the ultimate goal of contributing to the development of basic science in the 21st century. We are conducting highly sophisticated research by combining experiments and theories, time resolution and space resolution as analytical methods, analysis of phenomena and the creation of new materials. In other words, we explore the frontiers of basic chemistry as we seek to measure, analyze, evaluate, control and produce dynamic properties of molecules, develop molecular concepts, methodologies, new materials and new reactions for accelerating the evolution of chemistry, and aim at establishing new guiding principles of basic chemistry.

The Department of Chemistry has produced a great deal of important achievements in ultra-fast molecular spectroscopy, reactions in intense laser fields, synchrotron radiation time-resolved X-ray spectroscopy, catalyst surface science, molecular-electronic reaction control and new material creation, synthesis of neutral, single-component molecular metal, molecular engineering of supermolecular liquid crystals, as well as syntheses and analytical techniques based on these achievements. The COE program at the Department is pursued in cooperation with several researchers from other organizations, including the Research Centre for Spectrochemistry, the Laboratory for Earthquake Chemistry, the Graduate School of Frontier Sciences, the Graduate School of Engineering, and the Graduate School of Arts and Sciences. Thus, this COE program serves as a hub of academic exchanges among various chemistry-related organizations of the University of Tokyo.

12 laboratories

The Department of Chemistry has 12 laboratories for fundamental studies at the postgraduate level. These laboratories are divided into the three categories of physical chemistry, organic chemistry and inorganic/analytical chemistry.

Laboratory of Professor Hiroo Hamaguchi

Professor Hamaguchi has a mysterious habit of frequently traveling to India. Could it be because the “Raman effect” was discovered in that country? Vibration spectra such as the Raman spectrum and the infrared absorption spectrum, are sometimes referred to as “molecular fingerprints,” and reflect the uniqueness of each molecule. His lab is currently developing a time- and space-resolved Raman spectroscopy. Besides, the lab is studying the structures, functions and organizational mechanisms of various complex molecular organisms based on that method.

Laboratory of Professor Shin-ichi Ohkoshi

Professor Ohkoshi has just joined the Department, and is the youngest of all its professors. His lab has been trying to create new ferromagnetic materials with new material properties and functionalities, with the ultimate goal of opening up a new academic specialty in solid-state chemistry. The group succeeded in synthesizing for the first time a magnetic material that reverses its polarity twice over a temperature range, a magnetic material with a negative magnetic coercive force, and a magnetic material that responds to humidity (Figure 2). The group also succeeded in the first observation of photo-induced magnetic pole inversion and magnetization-induced third-harmonic generation.

Figure 2

Figure 2: Transformation from ferromagnetic to anti-antiferromagnetic through a drop in humidity. This takes place through switching of ferromagnetic 6-Coll-CrIII to antiferromagnetic 4-CoII-CrIII, resulting from the transformation of 6-cordination Coll into 4-cordination Coll.

Laboratory of Professor Kaoru Yamanouchi

Professor Yamanoichi specializes in intense laser field chemistry. It is quite an innovative subject, dealing with a new field for chemical reactions that is significantly different from the conventional concept of “perturbations.” When molecules are placed in an intense laser field, multiple electronic states will thoroughly intermingle (become degenerate), forming a distinct new state. This will bring about a variety of interesting phenomena, such as structural deformation, multiple ionization and Coulomb explosion. Professor Yamanouchi's laboratory studies the dynamic behaviors and reaction processes of these molecules and clusters.

Laboratory of Professor Yasuhiro Iwasawa

Currently serving as head of both the Department of Chemistry and the School of Science, Professor Iwasawa is leading an extremely busy life. His laboratory nonetheless maintains a calm and quiet atmosphere where the staff conducts remarkable research activities.

His lab's research program includes the designing and fine configuration of active catalyst surfaces; active surface structure analysis and surface reaction imaging analysis using a scanning probe microscope; and time-resolved analysis of surface structure and electronic state by X-ray absorption fine structure spectroscopy (Figure 3). Through spatial-temporal control of catalytic and surface reactions, the lab is attempting to discover the driving mechanism of dynamic chemical phenomena that take place on a surface which is supposed to be one of the most important questions in chemistry.

Figure 3

Figure 3: Time-resolved dispersive x-ray absorption fine structure (DXAFS) of the CO-absorption-induced declustering process with Rh/Al2O3 catalyst

Laboratory of Professor Takayuki Kawashima

The main research interest of the laboratory of Professor Kawashima is in synthesizing heteroatom compounds, i.e. organic compounds that include non-carbon elements in their structure. The properties and stability of heteroatom compounds including representative elements depend to a great extent on ligands. In consideration of the volume, rigidity, flexibility and electronic properties of molecules, the group designs and synthesizes ligands to occupy particular positions, ligands that respond to external stimuli and ligands for stereoscopic protection, and applies them to synthesis of heteroatom compounds containing representative elements.

Laboratory of Professor Koichi Narasaka

Professor Narasaka will be retiring next spring. Studies on methods for producing new active/reactive species lead to the development of new synthesis reaction processes that make use of them. Professor Narasaka's laboratory develops such new methods for producing active/reactive species and, by making use of them, seeks to achieve reactions that serve to configure carbon structures and nitrogen-containing complex heterocyclic structures, which are difficult to configure by conventional methods. The development of such reactions for binding and production helps to establish simple methods for synthesis of basic structures of important compounds used in pharmaceuticals, agricultural chemicals and functional materials (Figure 4).

Figure 4

Figure 4: Creation of reaction intermediate with oxime and the synthesis of catalytic nitrogen-containing cyclic compound

Laboratory of Professor Kazuo Tachibana

At the time of completion of his general education curriculum, Professor Tachibana faced a difficult choice between the Department of Chemistry and the Department of Mathematics. A group led by Professor Tachibana prolongs the activation of membrane protein using exogenous molecules such as those of a natural poison that has a strong affinity with such activation. In this way, the group obtains and analyzes information about its special configuration, to the end of understanding the structural factors that contribute to the activation of membrane protein.

Laboratory of Professor Eiichi Nakamura

Professor Nakamura seems to have been destined to become a professor of chemistry, as he is indeed talented both in research activities and education. It is the chemists' dream to comprehend the intrinsic natures of elements and molecules and to develop the methods to control their reactivity. Professor Nakamura's laboratory conducts research aimed at studying new reactions, new molecules and new principles in the field of organic chemistry that have the potential to make an impact in various fields of natural science and technologies. His laboratory specializes in the pursuit of studies for creating new materials that may have major impacts in chemistry-related fields (Figure 5).

Figure 5

Figure 5: Fulleren bilayer vesicle (top), bucky ferrocene (bottom left) and shuttlecock liquid crystal (bottom right)

Laboratory of Professor Tetsuya Hasegawa

Professor Hasegawa's laboratory is dedicated to solid-state chemistry. Solids, particularly those that constitute a strongly correlated inorganic system, manifest a variety of peculiar material properties such as superconductivity and magnetism. In most cases, these phenomena are caused by some “anomaly” in nano-scale electronic states. Using atomic layer control of thin film growth as a means to introduce such structures and organisms that are unobtainable under the thermal equilibrium state, the group continues to search for new functionalities and new material properties that may have significant impact.

Laboratory of Professor Yoshio Umezawa

Professor Umezawa will be retiring next spring. The purpose of the research program carried out at his lab is to develop methods that would make normally invisible objects visible, or normally immeasurable phenomena measurable. They pursue systematic development of optical probes that detect molecular processes for the transmission of cellular information, translate them into fluorescence or light signal in situ, and send the signal out from the cell. In addition, the lab has been developing STM tips and methods for selective visualization of chemical species and functional groups by means of intermolecular electron tunneling (Figure 6).

Figure 6

Figure 6: Principle of probes for the identification of protein localized in mitochondria. When the protein (orange) in contact with the N-end probe is transported into a mitochondrion, the C-end probe that is already in the mitochondrion reacts with DnaE, forming GFP through the splicing of protein.

Laboratory of Professor Hiroshi Nishihara

Professor Nishihara specializes in the creation of molecules whose properties change according to environmental factors such as light, electrical field, magnetic field or proton. His research project is of interest not only in terms of its importance as a subject for basic research, but also for its practical applications. The group aims at creating so-called “intelligent molecules” by producing new molecules with multiple sensitivities, composed of transition metal atoms and π-conjugated chains, and by using continuous interfaces that allow configuration control.

Laboratory of Professor Mitsuhiko Shionoya

Inspired by the relationship observed between the configuration of biopolymers and their function, Professor Shionoya has been attempting to create artificial biopolymers as molecules with new functionalities. Professor Shionoya's laboratory has been experimenting with new methods for synthesizing artificial DNAs and metal complex peptides by introducing metal ligand molecules into the configuration of target molecules (Figure 7).

Figure 7

Figure 7: Metal-complex type man-made DNA

Conclusion

For some time in the past, the word “chemistry” evoked negative associations such as contamination and harmful chemical substances. Such perceptions of the subject have proved to be a transient trend and today those who have deep insight into their surroundings clearly appreciate the fact that chemistry is a valuable branch of science, dedicated to the discovery and creation of materials that can be sources of well-being and comfort for human beings. With pride and a sense of responsibility, faculty members at the Department of Chemistry strive day and night to make significant contributions to chemical science.