Dr. Kiyoshi Takeda is interested in thermodynamic and spectroscopic properties of supercooled and glassy liquids in simple molecular substance. By combining the thermodynamic and spectroscopic studies, it is ivestigated from both macroscopic and microscopic viewpoints. Present research subjects are as follows.
Calorimeteric and thermoanalytical methods are applied to understand the relationship between kinetic and structural properties of supercooled and glassy liquids. We have found out the anomaous glass transition behavior in polyamine-polyalcohol mixture that shows an extremum in the intermediate concentration region, which is not observed for polyalcohol-polyalcohol mixture. This system would be unique and interesting system in which modulates its intermediate range structure as well as the short range one by means of the composition change.
Change in hydrogen bond structure in amine-alcohol mixture has been examined by means of the Raman scattering spectrocopyD
We have detected the non-additive relationship in stretching mode spectra of -OH and/or -NH2 groups which is caused by extra hydrogen-bond formation.
The Raman scattering study of vibrational states of -OH stretching mode has been measured for some alcoholic solutions containing inorganic ions, such as ClO4-.
The low energy vibrational modes in amorphous substances known as boson peak are studied by means of neutron scattering and calorimetric methods. The intensity and peak energy showed extrema as functions of concentration.