量子コンピュータの量子ビット素子としての分子磁性体の設計

• Project/Area Number: 15750120
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Functional materials chemistry
• Research Institution: Osaka University
• Principal Investigator: 川上 貴資 大阪大学, 理学研究科, 助手 (30321748)
• Project Period (FY): 2003 – 2005
• Project Status: Completed (Fiscal Year 2005)
• Budget Amount: ¥3,600,000 (Direct Cost: ¥3,600,000); Fiscal Year 2005: ¥700,000 (Direct Cost: ¥700,000); Fiscal Year 2004: ¥1,400,000 (Direct Cost: ¥1,400,000); Fiscal Year 2003: ¥1,500,000 (Direct Cost: ¥1,500,000)
• Keywords: 量子コンピュータ / 量子ドット素子 / 分子磁性 / 有機強磁性体 / 有機超伝導体 / 有機磁性金属 / 磁気的相互作用 / 有効交換積分

Research Abstract

量子コンピュータは、ごく近年にセンセーションを巻き起こしている。一方、分子磁性体は、我国にて世界に先駆けて発見された化学の重要な領域の一つである。そして、これらの融合として、量子コンピュータを分子磁性体にて実現することが考えられる。本研究では、「量子コンピュータの量子ビット素子としての分子磁性体の設計」を目指す。その実現のためには詳細な理論的議論からのアプローチも必要である。
平成17年度は、前年度に引き続き、実際の分子磁性体がその性能を発揮するための形態を、量子化学計算にて吟味し、合成戦略への設計指針を与えた。また加えて、量子ビット素子を分子磁性体にて構築するための理論展開に関しても、継続して行った。直接量子ビット素子の探索を行うのは非常に困難である。そこで、着実にアプローチするために、分子磁性体の分野での有機強磁性結晶及び分子性(超)伝導性結晶に関して、磁性スピン・遍歴電子の振る舞いを理論的に解析することから展開した。ここでは、磁気スピンが安定に存在する条件と、そのスピン源間の磁気的相互作用の発現メカニズムの解明を、磁性・伝導性に関する考察と一体となって押し進めた。

Research Products

• [Journal Article] Theoretical studies on magnetic interaction in one-dimensional CuBrn chains (2005)
  • Author(s): T.Kawakami
  • Journal Title: Synthetic Metals 154 Pages: 317-320
• [Journal Article] A Quantum Chemical Study on Magnetic Interactions in Phenzine-delivatives : for the Chemical-/Photo-induced Organic Magnets (2005)
  • Author(s): T.Taniguchi
  • Journal Title: Synthetic Metals 154 Pages: 321-324
• [Journal Article] Theoretical direct evaluation of inter-dimer J values in BETS salts (2005)
  • Author(s): T.Kawakami
  • Journal Title: Synthetic Metals 24 Pages: 2382-2388
• [Journal Article] A theoretical study of electronic structures and intermolecular magnetic interactions for spiro-biphenalenyls (2005)
  • Author(s): T.Taniguchi
  • Journal Title: Synthetic Metals 24 Pages: 2274-2279
• [Journal Article] Possibilities of magnetic modifications of DNA wires, sheets and related materials (2005)
  • Author(s): K.Yamaguchi
  • Journal Title: Synthetic Metals 24 Pages: 2758-2766
• [Journal Article] Theoretical studies on magnetic interactions and charge-dope effects in one-dimensional Ni5 and Ni7 complexes (2005)
  • Author(s): Y.Kitagawa
  • Journal Title: Synthetic Metals 24 Pages: 2751-2757
• [Journal Article] A theoretical study of zero-field splitting of organic biradicals (2005)
  • Author(s): M.Shoji
  • Journal Title: Synthetic Metals 24 Pages: 2708-2715
• [Journal Article] Theoretical studies on ferrimagnetic behavior of TCNE and manganese porphyrin dimer (2005)
  • Author(s): K.Koizumi
  • Journal Title: Synthetic Metals 24 Pages: 2720-2725
• [Journal Article] Theoretical studies on magnetic interactions between Ni(II) ions in urease (2005)
  • Author(s): Y.Maruno
  • Journal Title: Synthetic Metals 24 Pages: 2778-2783
• [Journal Article] Theoretical studies on dissociation of metal-carbon bond in Cobalamin : Formulation and calculation (2005)
  • Author(s): Y.Nishiyama
  • Journal Title: Synthetic Metals 24 Pages: 2745-2750
• [Journal Article] Possibilities of Molecular-based Spintoronics of DNA Wires, Sheets and Related Materials (2005)
  • Author(s): T.Kawakami
  • Journal Title: Int.J.Quant.Chem. 105 Pages: 655-671
• [Journal Article] Theory of Chemical Bonds in Metalloenzymes II : Hybrid-DFT Studies in iron-sulfur clusters (2005)
  • Author(s): M.Shoji
  • Journal Title: Int.J.Quant.Chem. 105 Pages: 628-644
• [Journal Article] Chemical Bonding, Less Screening, and Hund's Rule Revisited (2005)
  • Author(s): S.Yamanaka
  • Journal Title: Int.J.Quant.Chem. 105 Pages: 687-700
• [Journal Article] 紙上セミナー 分子磁性の理論(その13)有機強磁性高分子および有機強磁性金属の分子設計 (2005)
  • Author(s): 川上貴資
  • Journal Title: 固体物理 40 Pages: 855-869
• [Journal Article] 紙上セミナー 分子磁性の理論(その14)Cuoと等電子的なπ-d,π-Rおよび関連物質系の分子設計 (2005)
  • Author(s): 川上貴資
  • Journal Title: 固体物理 40 Pages: 931-946
• [Journal Article] Theoretical studies on magnetic interaction in one-dimensional spin chains of hydrogen atoms (Hn) and copper bromide (CunBrm). (2004)
  • Author(s): T.Kawakami
  • Journal Title: Int.J.Quant.Chem. 100 Pages: 907-917
• [Journal Article] Theoretical studies on effective exchange integrals using spin correlation function analysis and magnetic effective density functional (MEDF) method. (2004)
  • Author(s): Y.Kitagawa
  • Journal Title: Int.J.Quant.Chem. 100 Pages: 927-936
• [Journal Article] Theory of chemical bonds in metalloenzymes I : Analytical and hybrid-DFT studies on oxo and hydroxo diiron cores. (2004)
  • Author(s): M.Shoji
  • Journal Title: Int.J.Quant.Chem. 100 Pages: 887-906
• [Journal Article] Theoretical Studies on Electronic States of Rh-C60. Possibility of a Room temperature Organic Ferromagnet. (2004)
  • Author(s): S.Nakano
  • Journal Title: Molecules 9 Pages: 792-807
• [Journal Article] 分子磁性の理論(その3) 完全CI型波動関数法による有機磁性体の解析 (2004)
  • Author(s): 山中秀介
  • Journal Title: 固体物理 39 Pages: 509-519
• [Journal Article] 研究室紹介 (2004)
  • Author(s): 奥村光隆
  • Journal Title: 生産と技術 56 Pages: 35-38
• [Book] 実験化学講座12巻計算化学 (2004)
  • Author(s): 川上貴資
  • Total Pages: 492
  • Publisher: 丸善
• [Book] ナノ・IT時代の分子機能材料と素子開発 (2004)
  • Author(s): 川上貴資
  • Total Pages: 798
  • Publisher: NTS
• [Book] 物性機能量子化学入門 (2004)
  • Author(s): 山口兆
  • Total Pages: 288
  • Publisher: 講談社サイエンティフィック
• [Publications] T.Kawakami, et al.(1st author: "Theoretical determination of all the effective parameters in the BETS related crystals by HF and DFT methods."Synthetic Metals. 133-134. 565-567 (2003)
• [Publications] T.Kawakami, et al.(1): "Theoretical analysis of magnetic parameters between donors in BEDT-TTF, BETS, TMTTF and TMTSF crystals."Synthetic Metals. 137. 1259-1260 (2003)
• [Publications] T.Kawakami, et al.(1): "Theoretical studies of magnetic interactions in many types of organic donor salts : BEDT-TTF, BETS, TMTTF AND TMTSF."Polyhedron. 22. 2051-2065 (2003)
• [Publications] Y.Yamashita, et al.(2): "Theoretical studies on effective parameters for ionic radical clusters : possibility of organic magnetic metals."Synthetic Metals. 133-134. 589-591 (2003)
• [Publications] T.Taniguchi, et al.(2): "Theoretical studies of intra-and intermolecular magnetic interactions of organic polydradicals with S=1,2/3 and 2 spin sites."Synthetic Metals. 133-134. 585-587 (2003)
• [Publications] K.Yamaguchi, et al.(2): "Theoretical studies on molecule-based magnetic conductors."Polyhedron. 22. 2077-2090 (2003)
• [Publications] T.Taniguchi, et al.(3): "Theoretical study on model clusters for pure organomagnetic conductors."Synthetic Metals. 137. 1261-1262 (2003)
• [Publications] S.Nakano, et al.(3): "Theoretical studies on electronic states of Rh-C60."Synthetic Metals. 135-136. 779-780 (2003)
• [Publications] Y.Kitagawa, et al.(3): "Magnetic effective density functional studies on electronic states of Cr2(pyphos)4 and Pt2Cr2(pyphos)4(CH3)4."Polyhedron. 22. 2019-2025 (2003)
• [Publications] S.Nakano, et al.(3): "Hybrid DFT study of electronic structure on quasi-one-dimensional halogen-bridged binuclear metal complexes(MMX)."Polyhedron. 22. 2027-2038 (2003)
• [Publications] T.Taniguchi, et al.(3): "Theoretical study on pure organomagnetic conductors with model clusters."Polyhedron. 22. 2039-2043 (2003)
• [Publications] M.Shoji, et al.(3): "Hybrid density-functional theory stodies on stable polycarbenes."Polyhedron. 22. 2067-2076 (2003)
• [Publications] S.Yamanaka, et al.(3): "Spin correlation functions by generalized spin orbital density functional and multireference approaches."Int.J.Quant.Chem. 95. 512-520 (2003)
• [Publications] S.Yamanaka et al.(3): "Ab initio density functional approach for noncollinear molecular magnetism of multicenter metal clusters."(in press.).
• [Publications] R.Takeda, et al.(4): "Theoreticai studies on contributions of SOMO-SOMO and other couplings to the magnetic interaction in radical clusters."Synthetic Metals. 133-134. 593-595 (2003)
• [Publications] H.Isobe, et al.(4): "Systematic comparisons between broken symmetry and symmetry-adapted approaches to transition states by chemical indices : A case study of the Diels-Alder reactions."J.Phys.Chem.A. 107. 682-694 (2003)
• [Publications] K.Yamaguchi, et al.(5): "N-band Hubbard models II. Cooperative mechanisms of electron-phonon, electron correlation and many-band effects toward high-Tc superconductors."Int.J.Quant.Chem. 92. 47-70 (2003)
• [Publications] T.Matsumoto, et al.(6): "Synthesis, crystal structure and magnetic properties of dimethylthiotetrathiafulvalenoquinone-1,3-dithiolemethide/CuBr42-salt incorporating neutral copper bromide arrays."Synthetic Metals. 135-136. 575-576 (2003)
• [Publications] K.Yamaguchi, et al.(6): "Spin and pseudo spins in theoretical chemistry. A unified view for superposed and entangled quantum systems."Bull.Korean Chem.Soc.. 24(発表予定). (2003)
• [Publications] T.Matsumoto, et al.(7): "One-dimensional CuBr42-ion array and CuBr3-ion chain included in the p conducting framework composed of bis(methylthio)tetrathiafulvalenothioquinone-1,3-dithiocarbonatodithiolemethide Molecules."Inorg.Chem.. 42. 8638-8645 (2003)