1994 Fiscal Year Annual Research Report

分子磁性による反応制御

Research Project

Project/Area Number	04242107
Research Institution	The Institute of Physical and Chemical Research
Principal Investigator	林久治理化学研究所, 分子光化学研究室, 主任研究員 (50087508)
Co-Investigator(Kenkyū-buntansha)	山口益弘横浜国立大学, 工学部, 教授 (10018046) 住谷実静岡理工科大学, 理工学部, 助教授 (20201585) 中垣良一金沢大学, 薬学部, 助教授 (20159057) 秦憲典青山学院大学, 理工学部, 教授 (80082741) 谷本能文広島大学, 理学部, 助教授 (10110743)
Keywords	磁場効果 / 磁気同位体効果 / レーザー閃光法 / ラジカル対 / ^<73>Ge / 超伝導磁石 / Y_2Co_7H_x
Research Abstract	本研究班の研究目的は、外部磁場効果や磁気同位体効果などの、分子磁性による反応制御がどのような新しい反応系に拡張できるかを追求することにある。本年度の研究実績は次の通りである。林はナノ秒レーザー閃光法と超伝導磁石を用いて、三重項状態を経由する光水素移動反応を測定し、C-ラジカルのような軽原子ラジカルやS-ラジカルなどの重原子ラジカルの反応において、ラジカル対の寿命や散逸ラジカルの収量が0-2Tでは増加するが2-10Tでは減少するという、高磁場に特有な新しい磁場効果を多くの反応系で発見し、Gd^<3->の緩和促進効果を用いて、緩和機構とΔg機構の寄与を実験的に分離した。また、磁気同位体効果を用いて、^<73>Geを効率よく濃縮する条件を検討した。谷本は高スピン状態(S≧1)にある化合物の液相反応において磁場効果を見いだすことを目的として、m-Phenylene-bis-phenylmethyleneの77kにおける五重項-五重項ケイ光の寿命が0.5Tの磁場により30%減少することを01班と共同で見いだした。秦と中垣は液相化学反応における左右対称性の破れや磁場による不斉誘導を研究する目的で、アザ芳香族ニトリルと各種の光学活性カルボン酸との光化学反応における反応生成物の磁場効果と不斉誘導の可能性を更に厳密に検討した。気相反応の磁場効果に関しては、体系的理解がまだ完成していないので、住谷は気相反応の磁場効果の機構を解明する目的で、オゾンの^1B_2状態からの発光や酸素原子生成に対する磁場効果を研究したが磁場変化は観測されなかった。エチレンと酸素原子の反応では、三重項状態を経る反応経由が磁場強度に比例して減少し、0.8Tで約5%減少することを見いだした。山口は水素-金属系の平衡反応に対する磁場効果を研究し、Y_2Co_7H_xの電極電位は磁場強度に比例して減少し、15Tの磁場により0.5mV減少した。この値は熱力学的に予想される値に一致した。

Research Products
(18 results)

All Other

All Publications (18 results)

[Publications] Y.Nakamura: "Effects of high magnetic fields on the dynamic behavior of radical pairs generated in micellar solution." Chemical Physics Letters. 217. 387-392 (1994)
[Publications] G.Jeschke: "Magnetic field effects observed upon photolysis of para-substituted diphenyl disulfides in micellar solutions." The Journal of Physical Chemistry. 98. 4069-4075 (1994)
[Publications] M.Igarashi: "Magnetic field effects on the photochemical hydrogen abstraction of 2',3',4',5',6'-pentafluoroacetophenone in a Brij 35 micellar solution." Molecular Physics. 82. 1165-1179 (1994)
[Publications] M.Wakasa: "Paramagnetic quenching of the inverted magnetic field effects observed in the photoreduction of decafluorobenzophenone in a micellar solution." Chemistry Letters. 1941-1944 (1994)
[Publications] M.Wakasa: "Magnetic field effect on the dynamic behavior of a radical pair involving an Sn-centered radical." Chemical Physics Letters. 229. 122-126 (1994)
[Publications] M.Wakasa: "Separation of magnetic field effects on the photoreduction of xanthone with p-aminothiophenol into the effects due to the g ---." Molecular Physics. 83. 613-618 (1994)
[Publications] Y.Tanimoto: "A laser flash photolysis study of magnetic field effects on the hydrogen abstraction reaction of xanthone from xanthene in micellar celution." Journal of Photochemistry and Photobiology A. 79. 89-94 (1994)
[Publications] H.Tomioka: "Chemistry and kinetics of α-and β-naphthyl(phosphonyl)carbenes.Effects of positions on neibouring phosphonate participation." Journal of Chemical Society,Perkin Trans.2. 633-641 (1994)
[Publications] M.Fujiwara: "Mechanism of o-methylbenzyl radical by photodissociation of o-xylene in solution." The Journal of Physical Chemistry. 98. 5695-5700 (1994)
[Publications] Y.Fujiwara: "Does a magnetic field induce optical activity in photochemical reaction of 4-methyl-2-guinolinecarbonitrile with optically active(S)-(+)-2-phenylpropionic Acid ?" Bulletin of the Chemical Society of Japan. 67. 2577-2579 (1994)
[Publications] N.E.Polyakov: "Product-yield-detected ESR study on the dynamic benavior of radical pairs generated in photoreduction of acetylenic ketones in SDS micellar solution." The Journal of Physical Chemistry. 98. 10563-10567 (1994)
[Publications] M.Mukai: "A laser flash photolysis study of electron transfer processes of [Ru(bpy)_3]^<2+>in high magnetic field." Bulletin of the Chmical Society of Japan. 67. 3112-3115 (1994)
[Publications] R.Nakagaki: "Magnetic field effects upon photochemistry of benzophenone-carboxylate esters." Zeitschrift fur Physikalische Chemie. 182. 255-261 (1993)
[Publications] R.Nakagaki: "Hydrogen bonding of aromatic amines in hvdroxylic solvents 2.Absorption and emission spectroscopy of substituted 7-amino-coumarine and 7-aminocarbostyrils." Journal of Photochemistry and Photobiology A. 80. 113-119 (1994)
[Publications] R.Nakagaki: "Comment on “photochemical reaction of 4-methyl-2-quinolinecarbonitrile with optically active(S)-or (R)-2-phenylpropionic acid.The magnetic field---"" Chemical Physics. 67. 86-92 (1994)
[Publications] R.Nakagaki: "Magnetic field effects on reaction yields for photochemistry involving biradical intermediates." Magnetic Resonance in Medicine.6. 404-406 (1995)
[Publications] R.Nakagaki: "External magnetic field and magnetic isotope effects upon lifetimes of biradicals derived from benzophenone derivatives." Chemical Physics Letters. 233. 41-46 (1995)
[Publications] T.Goto: "Itinerant metamagnetism of the Co-sublattice in the Y_<1-x>Nd_xCo_3system in ultrahigh magnetic fields up to 110 T." Physica B. 193. 10-16 (1994)

1994 Fiscal Year Annual Research Report

分子磁性による反応制御

Principal Investigator

林 久治 理化学研究所, 分子光化学研究室, 主任研究員 (50087508)

Research Products

[Publications] Y.Nakamura: "Effects of high magnetic fields on the dynamic behavior of radical pairs generated in micellar solution." Chemical Physics Letters. 217. 387-392 (1994)

[Publications] G.Jeschke: "Magnetic field effects observed upon photolysis of para-substituted diphenyl disulfides in micellar solutions." The Journal of Physical Chemistry. 98. 4069-4075 (1994)

[Publications] M.Igarashi: "Magnetic field effects on the photochemical hydrogen abstraction of 2',3',4',5',6'-pentafluoroacetophenone in a Brij 35 micellar solution." Molecular Physics. 82. 1165-1179 (1994)

[Publications] M.Wakasa: "Paramagnetic quenching of the inverted magnetic field effects observed in the photoreduction of decafluorobenzophenone in a micellar solution." Chemistry Letters. 1941-1944 (1994)

[Publications] M.Wakasa: "Magnetic field effect on the dynamic behavior of a radical pair involving an Sn-centered radical." Chemical Physics Letters. 229. 122-126 (1994)

[Publications] M.Wakasa: "Separation of magnetic field effects on the photoreduction of xanthone with p-aminothiophenol into the effects due to the g ---." Molecular Physics. 83. 613-618 (1994)

[Publications] Y.Tanimoto: "A laser flash photolysis study of magnetic field effects on the hydrogen abstraction reaction of xanthone from xanthene in micellar celution." Journal of Photochemistry and Photobiology A. 79. 89-94 (1994)

[Publications] H.Tomioka: "Chemistry and kinetics of α-and β-naphthyl(phosphonyl)carbenes.Effects of positions on neibouring phosphonate participation." Journal of Chemical Society,Perkin Trans.2. 633-641 (1994)

[Publications] M.Fujiwara: "Mechanism of o-methylbenzyl radical by photodissociation of o-xylene in solution." The Journal of Physical Chemistry. 98. 5695-5700 (1994)

[Publications] Y.Fujiwara: "Does a magnetic field induce optical activity in photochemical reaction of 4-methyl-2-guinolinecarbonitrile with optically active(S)-(+)-2-phenylpropionic Acid ?" Bulletin of the Chemical Society of Japan. 67. 2577-2579 (1994)

[Publications] N.E.Polyakov: "Product-yield-detected ESR study on the dynamic benavior of radical pairs generated in photoreduction of acetylenic ketones in SDS micellar solution." The Journal of Physical Chemistry. 98. 10563-10567 (1994)

[Publications] M.Mukai: "A laser flash photolysis study of electron transfer processes of [Ru(bpy)_3]^<2+>in high magnetic field." Bulletin of the Chmical Society of Japan. 67. 3112-3115 (1994)

[Publications] R.Nakagaki: "Magnetic field effects upon photochemistry of benzophenone-carboxylate esters." Zeitschrift fur Physikalische Chemie. 182. 255-261 (1993)

[Publications] R.Nakagaki: "Hydrogen bonding of aromatic amines in hvdroxylic solvents 2.Absorption and emission spectroscopy of substituted 7-amino-coumarine and 7-aminocarbostyrils." Journal of Photochemistry and Photobiology A. 80. 113-119 (1994)

[Publications] R.Nakagaki: "Comment on “photochemical reaction of 4-methyl-2-quinolinecarbonitrile with optically active(S)-or (R)-2-phenylpropionic acid.The magnetic field---"" Chemical Physics. 67. 86-92 (1994)

[Publications] R.Nakagaki: "Magnetic field effects on reaction yields for photochemistry involving biradical intermediates." Magnetic Resonance in Medicine.6. 404-406 (1995)

[Publications] R.Nakagaki: "External magnetic field and magnetic isotope effects upon lifetimes of biradicals derived from benzophenone derivatives." Chemical Physics Letters. 233. 41-46 (1995)

[Publications] T.Goto: "Itinerant metamagnetism of the Co-sublattice in the Y_<1-x>Nd_xCo_3system in ultrahigh magnetic fields up to 110 T." Physica B. 193. 10-16 (1994)

林久治理化学研究所, 分子光化学研究室, 主任研究員 (50087508)