We study on multi-disciplinary and practically basic researches of materials in Solid State Science, Chiral Science, and Crystal Optics bridging among Physics, Chemistry, and Life Science. Particularly, we attempt to reveal optical, physico-chemical, and cell-biological properties of organic and inorganic crystals, pharmaceuticals, self-assembly compounds and proteins

·Chiroptical researches by using the G-HAUP

Measuring chiroptical properties such as circular dichroism (CD) and optical activity (OA), which are a real and an imaginary part of antisymmetric components of a dielectric permittivity tensor respectively, has attracted a great interest because these provide valuable information on asymmetry and/or dissymmetry of molecular and crystal structure and also on the spatial dispersion of atoms positions.  However, it had been difficult to measure the chiroptical properties in solid state because the observed OA and CD signals are overwhelmed by 100 – 1,000 times larger optical anisotropy signals such as linear birefringence (LB) and linear dichroism (LD).  We have developed the generalized-high accuracy universal polarimeter (G-HAUP) method, which enables us to simultaneously measure wavelength and temperature dependences of OA, CD, LB and LD in absorbent anisotropic media.  We revealed new insights related to the structural phase transition and domain structure of ferroelectric crystals and determined the absolute chirality of amino acid and protein crystals by using the G-HAUP.  Recently, we have applied the G-HAUP as collaborative researches to Bi-based Cu oxide high temperature superconductors, self-assembly complexes such as (12,8)-[4]CC isomers and chiral crystals in order to understand the relationship between various physical properties and chiral optical properties.

·Photomechanical crystals

The research on photomechanical bending firstly reported in 2007 has changed our common sense that molecular crystals are rigid and brittle. We have researched on photomechanical functions of molecular crystals of photochromic compounds, and also recently discovered locomotion behaviors induced by thermal phase transition. This project focuses on the diversification of photo- and thermo-induced mechanical functions of molecular crystals. We are working on this project with Prof. Koshima of Research Organization for Nano & Life Innovation.

·Reversible photoreactions in self-assembly

Reversibly polymerizable molecules via photoreactions are expected to reduce carbon consumption in our society through its recycling. However, the photopolymerization reactions have been limited to crystal environments so far. We are aiming to expand the possibility into self-assembly. This project is a collaborative work with Assoc. Prof. Saito of Monash University.

·Research on Chirality of Pharmaceuticals

We investigate the relationship between the chirality and structure of chiral pharmaceuticals such as Thalidomide that is a therapeutic drug of multiple myeloma and reveal the racemic reaction mechanism with chiral inversion of chiral pharmaceuticals from a viewpoint of activation energy.

·Analysis of molecular mechanism of neuropsychiatric diseases

We are working with Prof. Sawamura of Research Organization for Nano & Life Innovation, for elucidation of the molecular mechanism in mental retardation and its treatment with thalidomide by functional analysis of the cereblon protein involved in the onset of neuropsychiatric disease.