Condensed Molecular Materials Laboratory

Synthesis, characterization and design of molecular materials, especially molecular metals ( superconductors ), have been undertaken. Molecular conductors exhibit a variety of physical properties which can be systematically understood on the basis of "simple" and "clear" electronic structures. From a chemical point of view, the most fascinating character of the molecular conductor is its "designability", that is, we can finely control solid state properties with chemical modifications of the molecule. The newly synthesized materials are characterized by the X-ray diffraction method and physical measurements (electrical conductivity, etc.). The electronic structure is investigated by the simple band structure calculation. All these results are devoted to the design of new molecular materials.

Research Subjects

• Construction and Electronic Properties of New Supramolecular Assemblies
• Physical and Chemical Control of the Electronic State of the Molecular Conductor
• Interrelation between the Crystal Structure and the Electrical Property

Publications

1. Kusamoto, T., Yamamoto, H. M., Tajima, N., Oshima, Y., Yamashita, S., Kato, R.:
   "Bilayer Mott System Based on Ni(dmit)2 (dmit = 1,3-dithiole-2-thione-4,5-dithiolate) Anion Radicals: Two Isostructural Salts Exhibit Contrasting Magnetic Behavior"
   Inorg. Chem., 51, 11645-11654 (2012)
2. Kiss, T., Chainani, A., Yamamoto, H. M., Miyazaki, T., Akimoto, T., Shimojima, T., Ishizaka, K., Watanabe, S., Chen, C. T., Fukaya, A., Kato, R., and Shin, S.:
   "Quasiparticles and Fermi Liquid Behaviour in an Organic Metal"
   Nature Communications, 3, 1089/1-6 (2012)
3. Tajima, N., Kato, R., Sugawara, S., Nishio, Y., and Kajita, K.:
   "Interband Effects of Magnetic Field on Hall Conductivity in the Multilayered Massless Dirac Fermion System α-(BEDT-TTF)2I3"
   Phys. Rev. B, 85, 033401/1-4 (2012)
4. Yamamoto, T., Nakazawa, Y., Tamura, M., Nakao, A., Ikemoto, Y., Moriwaki, T., Fukaya, A., Kato, R., and Yakushi, K.:
   "Intradimer Charge Disproportionation in Triclinic-EtMe3P[Pd(dmit)2]2 (dmit: 1,3-Dithiole-2-thione-4,5-dithiolate)"
   J. Phys. Soc. Jpn., 80, 123709/1-4 (2011)
5. Kawasugi, Y., Yamamoto, H. M., Tajima, N., Fukunaga, T., Tsukagoshi, K., and Kato, R.:
   "Electric-Field-Induced Mott Transition in an Organic Molecular Crystal"
   Phys. Rev. B, 84, 125129/1-9 (2011)
6. Yamamoto, T., Nakazawa, Y., Tamura, M., Fukunaga, T., Kato, R., and Yakushi, K.:
   "Vibrational Spectra of [Pd(dmit)2] Dimer (dmit = 1,3-dithiole-2-thione-4,5-dithiolate): Methodology for Examining Charge, Inter-Molecular Interactions, and Orbital"
   J. Phys. Soc. Jpn., 80, 074717/1-16 (2011)
7. Hazama, K., Uji, S., Takahide, Y., Kimata, M., Satsukawa, H., Harada, A., Terashima, T., Kosaka, Y., Yamamoto, H. M., and Kato, R.:
   "Fermi Surface and Interlayer Transport in the Two-Dimensional Magnetic Organic Conductor (Me-3,5-DIP)[Ni(dmit)2]2"
   Phys. Rev. B, 83, 165129/1-9 (2011)
8. Yamashita, S., Yamamoto, T., Nakazawa, Y., Tamura, M., and Kato, R.:
   "Gapless Spin Liquid of an Organic Triangular Compound Evidenced by Thermodynamic Measurements"
   Nature Communications, 2, 275/1-6 (2011)
9. Yamashita, M., Nakata, N., Senshu, Y., Nagata, M., Yamamoto, H. M., Kato, R., Shibauchi, T., and Matsuda, Y.:
   "Highly Mobile Gapless Excitations in a Two-Dimensional Candidate Quantum Spin Liquid"
   Science, 328(5983), 1246-1248 (2010)
10. Kawasugi, Y., Yamamoto, H. M., Tajima, N., Fukunaga, T., Tsukagoshi, K., and Kato, R. :
    "Field-Induced Carrier Delocalization in the Strain-Induced Mott Insulating state of an Organic Superconductor"
    Phys. Rev. Lett., 103(11), 116801/1-4 (2009)