Hisao Nishi

Langmuir-Blodgett films of octa-alkyl phthalocyanines

Abstract Phthalocyanine (Pc) derivatives attached directly to eight alkyl chains were synthesized. The Pc monolayers were spread on water from toluene solution and were transferred onto solid plates using the horizontal lifting method. The polarized visible and IR spectra of the multilayers, the film thickness and the molecular areas of the monolayers showed that Pc macrocycles were oriented nearly parallel to the surface. Reversible electrochromism was observed for the Pc multilayers on indium-tin oxide (ITO) electrodes in an aqueous solution of KCl.

Effect of Solvent Polarity and Acidity on Fluorescence Emission Fine Structures of Select Aza-Polynuclear Aromatics and Dibenzo[b,n]Perylene Hetero-Atom Derivatives

Fluorescence emission spectra are reported for 1-azabenz[a]anthracene, 2-azabenz[a]anthracene, 9-azabenz[a]anthracene, 4-azachrysene, 1,2,7,8-tetraazacoronene, dibenzo[2,3:10,11]perylo[1,12bcd]furan, dibenzo[2,3:10,11]perylo[1,12bcd]thiophene, and dibenzo[2,3:10,11]perylo[1,12bcd] selenophene dissolved in various organic solvents. Results of these measurements are used to classify the solutes into probe or nonprobe molecules depending upon whether emission intensity ratios vary systematically with solvent polarity. Of the eight aromatic solutes examined, only the three azabenzanthracenes showed slight probe character.

Synthesis of Octasubstituted Metal Naphthalocyanines

Abstract Naphthalocyanine metal complexes attached to chalcogen atoms between the naphthalocyanine ring and phenyl or alkyl groups were synthesized.

Structure and Absorption Spectra of Thin Films of Tripmenodithiazine, C18N2S2H10

Abstract A crystal structure of triphenodithiazine (TPDT) has been determined by the X-ray diffraction of a single crystal; Crystal data were monoclinic, space group P21/c, a= 10.4814(12) A, b= 5.4203(7) A, c= 12.3871(17) A, β = 107.554 (10)°, V= 670.969 A3 and Z= 2. The X-ray diffractions of the powder and the thin film of the compound have also been studied at room temperature. Sharp diffraction lines of the thin film with thickness of 500 A, 100, 200, 500 and 600 lines were found. The TPDT molecules in this film arrange along the a*-axis perpendicular to the substrate. The absorption spectra of several thin films with thickness of 150 A, 500 A, 700 A, 900 A and 1200 A have been studied at room temperature. The spectra of thin films were very sensitive to the molecular arrangement. A new sharp absorption band at around 686 nm was observed for the oriented films of the 500 A, 700 A and 900 A. This behavior observed in the oriented film may arise from the Davydov splitting. When the oriented film of TPDT ...

ANOMALOUS ABSORPTION SPECTRA OF HIGHLY ORIENTED THIN FILMS OF TRIPHENOTHIASELENAZINE

Abstract X-ray diffraction and absorption spectra of evaporated thin films of triphenothiaselenazine (TPTS) have been studied at room temperature. The X-ray diffraction pattern of the 900 A film of TPTS comprises harmonic lines assigned to the n00 (n=1, 2, 3, 4, 5, 6 and 7) reflections. TPTS molecules in this film orient highly and arrange along the a ∗ -axis perpendicular to a substrate. An anomalous absorption band at around 800 nm was found for the 900 A film of TPTS with sharp diffraction lines of the seventh order. This may be due to the strong intermolecular interaction in the highly oriented film.

Lateral intermolecular interaction in Langmuir-Blodgett films of octa-alkyl hydrogen phthalocyanines

Abstract Piezomodulated absorption spectra of Langmuir-Blodgett films of (C 8 H 17 ) 8 H 2 Pc and (C 12 H 25 ) 8 H 2 Pc were measured at 100 K. The separations of four absorption bands (1.60, 1.64, 1.76 and 2.05 eV) are increased by a uniaxial compressive stress applied along the film plane. These spectral features are explained by assuming lateral interactions among the π electrons of the H 2 Pc rings which are parallel to the surface.

Molecular organization and electrical behaviors in LB films of phthalocyanine derivatives containing eight alkyl chains

Phthalocyanine derivatives substituted with eight alkyl chains take an orientation of the macrocycle nearly parallel and of the hydrocarbons almost vertical to the surface in the LB films. Remarkable anisotropy of the electrical conductivities and frequency dependence of the normal conductivity were observed in these LB films.

SYNTHESES AND PROPERTIES OF TRIPHENODIOXAZINES CONTAINING PHENOTHIAZINE RING

従来,優れた紫色有機顔料として N-エチルカルバゾールジオキサジン[A]が知られている。この化合物のカルバゾール環の代わりに,種々の炭素多環または複素多環核を融合すれば,新しいタイプの深色で濃色な有機顔料の創製が期待できる。この研究ではフェノチアジン環を融合したトリフェノジオキサジンを[A]の場合と同様な経路により合成し,構造を確定した。多環縮合物中間体から閉環する場合,閉環位置に二通りあり,線形構造をとる場合と非線形構造をとる場合が考えられる。この研究ではフェノチアジン環をもつ場合には縮合物中間体から線形に脱水素閉環し,フェノチナジン=S,S-ジオキシドの場合は縮合物中間体から非線形に脱水素閉環した。後者の場合,あらかじめ閉環ぎ予定位置にメトキシル基を導入しておき,縮合物中間体から脱メタノール閉環して線形化合物を得た。予期したように,これらの色素は紫ないし青緑色で,ポリエチレン材料の者色材として用いれば淡色であるが優れた性質を示すと評価された。