2002 Fiscal Year Annual Research Report

dd及びdπ共役電子系の物性・機能発現に関する基礎理論の構築と物質設計への展開

Research Project

Project/Area Number	00J01877
Research Institution	Osaka University
Principal Investigator	北河康隆大阪大学, 大学院・理学研究科, 特別研究員(DC1)
Keywords	MEDF法 / 一次元金属錯体 / 集積型金属錯体 / d-d共役電子系 / pπ-dπ電子系 / 量子化学計算 / 磁気的相互作用 / 有効交換積分値
Research Abstract	Pt_2Cr_2(pyphos)_4(CH_3)_4錯体およびCr_2(pyphos)_4錯体は一次元的に配列した金属中心を持ち、一般的なCr(II)_2四重結合に比べて非常に弱い有効交換積分値(J_<ab>値)を示す事が知られている。本年はこれらの錯体の電子状態を、Cr間に働く磁気的な相互作用を手がかりとして考察する事を試みてきた。具体的には、改良した密度汎関数法;MEDF(magnetice effective density functional)法を用いて求められたCr間のJ_<ab>値と実験値とを比較した。その結果、Pt、Cr共に形式電荷を二価と仮定すると、実験値をうまく説明できない事が明らかになった。そこで本研究では、錯体中の金属が他の価数をとりうると仮定してJ_<ab>値を見積もり、実験値と比較する事により錯体中のCrの電荷及び錯体の電子状態を考察した。本研究では、この錯体の配位子を取り除いたモデルを用い、幾つかのCrの形式電荷と電子状態を仮定し、J_<ab>値を計算し実験値と比較する事により、錯体のとりうる電子状態を絞った。次にその結果を元に、Cr_2(pyphos)_4やPt_2Cr_2(pyphos)_4(CH_3)_4錯体でのフルモデルでのJ_<ab>値を求め実験値と比較し、錯体の電子状態を決定した。得られたMolecular orbitalやNatural orbital、軌道エネルギー等から、錯体の金属中心付近の電子状態を考察した。また、代表的な二核および四核錯体の計算結果と比較することにより、両端のPtが中心Cr間の磁気的な相互作用に及ぼす効果を考察した。

Research Products
(13 results)

All Other

All Publications (13 results)

[Publications] Y.Kitagawa et al.: "Instability of a system and its estimation in terms of the hybrid density functional theory method, A magnetic effective density functional (MEDF) approach"Molecular Physics. 100. 1829-1838 (2002)
[Publications] Y.Kitagawa et al.: "Theoretical Studies on Magnetic Interactions of Aligned Tetrametal Systems by Using Magnetic Effective Density Functional (MEDF) Method"Mol. Cryst. Liq. Cryst. 379. 525-530 (2002)
[Publications] Y.Kitagawa et al.: "Theoretical Studies on Magnetic Interactions of Aligned Tetrametal System by Using Hybrid Density Functional Method"Mol. Cryst. Liq. Cryst. 376. 347-352 (2002)
[Publications] K.Yamaguchi et al.: "Spin-mediated superconductivity in cuprates, organic conductors and pi-d conjugated systems"Coord. Chem. Rev. 226. 235-259 (2002)
[Publications] H.Isobe et al.: "Extended Hartree-Fock (EHF) theory of chemical reactions VI : hybrid DFT and post-Hartree-Fock approaches for concerted and non-concerted transition structures of the Diels-Alder reaction"Molecular Physics. 100. 717-727 (2002)
[Publications] Y.Takano et al.: "Theoretical studies of magnetic interactions in Mn(II)(hfac)(2){di(4-pyridyl)phenylcarbene} and Cu(II)(hfac)(2){di(4-pyridyl)phenylcarbene}"J. Am. Chem. Soc. 124. 450-461 (2002)
[Publications] K.Yamaguchi et al.: "Analytical and ab initio studies of effective exchange interactions, polyradical character, unpaired electron density and information entropy in radical clusters (R)(N) : Allyl radical cluster (N=2-10) and hydrogen radical cluster (N=50)"Int. J. Quant. Chem. 90. 370-385 (2002)
[Publications] T.Kawakami et al.: "Theoretical studies on pi-d magnetic interactions between BETS donor and transition metal halides in kappa-BETS2MX4 crystals"Mol. Cryst. Liq. Cryst. 379. 484-494 (2002)
[Publications] H.Nagao et al.: "Field-induced superconductivity"Mol. Cryst. Liq. Cryst. 379. 495-500 (2002)
[Publications] S.Nakano et al.: "Theoretical studies on SDW and CDW states of Cu and Ag oxyides under the periodic boundary condition"Mol. Cryst. Liq. Cryst. 379. 513-518 (2002)
[Publications] T.Kawakami et al.: "Theoretical investigation of magnetic parameters in two-dimensional sheets of pure organic BEDT-TTF and BETS molecules by using ab initio MO and DFT methods"Molecular Physics. 100. 2641-2652 (2002)
[Publications] T.Onishi et al.: "Theoretical study on the magnetic interaction for manganese oxides"Mol. Cryst. Liq. Cryst. 376. 335-340 (2002)
[Publications] T.Kawakami et al.: "Theoretical studies on magnetic properties of TCNQ organic crystals with ab initio and DFT methods"Mol. Cryst. Liq. Cryst. 376. 441-416 (2002)

2002 Fiscal Year Annual Research Report

dd及びdπ共役電子系の物性・機能発現に関する基礎理論の構築と物質設計への展開

Principal Investigator

北河 康隆 大阪大学, 大学院・理学研究科, 特別研究員(DC1)

Research Products

[Publications] Y.Kitagawa et al.: "Instability of a system and its estimation in terms of the hybrid density functional theory method, A magnetic effective density functional (MEDF) approach"Molecular Physics. 100. 1829-1838 (2002)

[Publications] Y.Kitagawa et al.: "Theoretical Studies on Magnetic Interactions of Aligned Tetrametal Systems by Using Magnetic Effective Density Functional (MEDF) Method"Mol. Cryst. Liq. Cryst. 379. 525-530 (2002)

[Publications] Y.Kitagawa et al.: "Theoretical Studies on Magnetic Interactions of Aligned Tetrametal System by Using Hybrid Density Functional Method"Mol. Cryst. Liq. Cryst. 376. 347-352 (2002)

[Publications] K.Yamaguchi et al.: "Spin-mediated superconductivity in cuprates, organic conductors and pi-d conjugated systems"Coord. Chem. Rev. 226. 235-259 (2002)

[Publications] H.Isobe et al.: "Extended Hartree-Fock (EHF) theory of chemical reactions VI : hybrid DFT and post-Hartree-Fock approaches for concerted and non-concerted transition structures of the Diels-Alder reaction"Molecular Physics. 100. 717-727 (2002)

[Publications] Y.Takano et al.: "Theoretical studies of magnetic interactions in Mn(II)(hfac)(2){di(4-pyridyl)phenylcarbene} and Cu(II)(hfac)(2){di(4-pyridyl)phenylcarbene}"J. Am. Chem. Soc. 124. 450-461 (2002)

[Publications] T.Kawakami et al.: "Theoretical studies on pi-d magnetic interactions between BETS donor and transition metal halides in kappa-BETS2MX4 crystals"Mol. Cryst. Liq. Cryst. 379. 484-494 (2002)

[Publications] H.Nagao et al.: "Field-induced superconductivity"Mol. Cryst. Liq. Cryst. 379. 495-500 (2002)

[Publications] S.Nakano et al.: "Theoretical studies on SDW and CDW states of Cu and Ag oxyides under the periodic boundary condition"Mol. Cryst. Liq. Cryst. 379. 513-518 (2002)

[Publications] T.Kawakami et al.: "Theoretical investigation of magnetic parameters in two-dimensional sheets of pure organic BEDT-TTF and BETS molecules by using ab initio MO and DFT methods"Molecular Physics. 100. 2641-2652 (2002)

[Publications] T.Onishi et al.: "Theoretical study on the magnetic interaction for manganese oxides"Mol. Cryst. Liq. Cryst. 376. 335-340 (2002)

[Publications] T.Kawakami et al.: "Theoretical studies on magnetic properties of TCNQ organic crystals with ab initio and DFT methods"Mol. Cryst. Liq. Cryst. 376. 441-416 (2002)

北河康隆大阪大学, 大学院・理学研究科, 特別研究員(DC1)