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For the purpose of improving the visible method of γ-rays detection, detailed conditions with various acids have been examined for the color development of a fluoran-based black color former in acetonitrile. It is suggested that the protons (H + ), which may be produced from acid generators by γ-ray radiation, can be properly detected by the color development of the black color former containing proper kinds and concentrations of bases. Reversible decolorization through the interaction between Mg 2+ and polyamines (acyclic and macrocyclic) has been examined in order to reconfirm that the colored zwitterion is produced by the direct chemical interaction with Mg (ClO 4 ) 2 in the fluoran dye–acetonitrile solution.

チオフェン系アゾ色素は対応する置換アゾベンゼンより長波長側に吸収を示す。この現象（深色性）を明らかにする目的でベンゼン、チオフェン、フラン、ピロール、シクロペンタジエンおよびこれらのアザ置換体からなるアゾ化合物について量子化学計算をおこなった。まず、AM1、PM3、DFT計算によりそれぞれの安定配座を推定した。ついでチオフェン系アゾ化合物について硫黄原子の3d-AOを含めた場合と含めない場合のCNDO/S計算を行い、最長波長吸収帯に対する3d-AOの寄与は無視し得ることが確認された。さらに、CNDO/S法およびTD-DFT法によりスペクトル計算をおこなった。その結果、チオフェン系アゾ化合物が特異的に深色性を示すのではなく五員環系アゾ色素に共通した特性であることが示唆された。

Relationships between the HOMO energy and σ(p) in ylides 1-14 have been studied. Linear relationships between the HOMO energies obtained by HF/3-21G[*] and 6-31G*, BLYP/6-31G*, and B3LYP/6-31G* methods and the substituent constant (σ(p)) were found, respectively. Hence, for the electron donation of the ylide, it is noted that the HOMO energy can be used as a new parameter for predicting the basicity of SN ylides. By comparing the results obtained by these calculations, the best method is found to be B3LYP/6-31G*. The results of bond lengths and torsion angles obtained by DFT calculations correspond with that of X-ray structure determinations.

We report here a novel method of visualization to record Born's probability densities in glass blocks by the use of a recently developed three-dimensional laser technique. Conventional visualization methods cannot simultaneously show all the characteristic features of an atomic orbital, whereas a real image in a glass block in the present study allows us to recognize both the shape of the orbital and its wave character, such as the existence of spherical, planar and/or conical nodes, at the same time. One can take this block in one's hands and observe it from an arbitrary direction, to gain clearly the whole image of probability density in it. To show a physical image of the behavior of an electron in an atom is profitable for the understanding of atomic orbitals. This method is the most appropriate to understand images of "the probability density".

Symmetry elements in various hydrogen atomic orbitals are summarized with respect to quantum numbers n, l and m. The results are useful to improve the efficiency of drawing the isosurfaces of these orbitals.

Relationships between the HOMO energy, the ν(C=O) stretching band, basicity(pKa), and σ(p) in phosphorus ylides have been studied. A linear relationship between the HOMO energies obtained by the AM1, HF/3-21G, and HF/6-31G methods and pKa was found. The same linear relationship was found between the HOMO energies obtained by these methods and σ(p)(indicated p-position). Thus, the HOMO energy can be adopted instead of pKa and σ(p) for choosing the ylide as the donor in organic reactions. In addition, a linear relationship between the ν (C=O) stretching bands obtained by these methods and the parameters described above was found. Hence, as for the electron donation of the ylide, it is noted that the HOMO energy can be used instead of pKa as a new method for showing the basicity of ylides. Furthermore, the ν(C=O) stretching bands obtained by these methods can be estimated by the HOMO energy obtained by the same methods.

A film device to visualize UV irradiation was successfully fabricated by an agarose solid film containing Fluoran dye, acid generator N-tosyloxyphthalimide and 2-propanol medium, and the mechanism and kinetics of this system were investigated. The reactions involving: (1) acid generation from N-tosyloxyphthalimide by UV irradiation, (2) acid generation from N-tosyloxyphthalimide by chemical amplitude reaction, (3) coloring reaction of Fluoran dye by acid were analyzed by changing the Fluoran dye concentration. The concentration of the colored Fluoran dye was determined by the absorbance at 520 nm appearing by UV irradiation. The kinetic constants of the three reactions were estimated by solving the differential equations by the formation of the colored Fluoran dye with changing the parameters based on a least square method. The result was in accordance with the experimental results to give reaction rate constants of the processes.

A leuco crystal violet analog, tris(4-N, N-dimethylaminophenyl)methanethiol (1) was synthesized and utilized to the γ rays detection system. Acetonitrile solution of leuco dye 1 showed significant absorbance change after γ irradiation of 1 Gy, and the change was more significant than those of tris(4-N, N-dimethylaminophenyl)methanol (2) and leuco crystal violet (3).

A novel phenoxazine color former, 3, 7-bis(N, N-diethylamino)-10-(2, 2, 2-trichloroethoxycarbonyl)phenoxazine (1), was synthesized. Acetonitrile solution of colorless 1 was observed to give blue cation 2a by γ irradiation of 10 Gy. Little absorbance changes were observed when the blue shade solution was kept for 6 d after γ irradiation. Compound 1 showed excellent sensitivity to γ rays and the resulting cation 2a was stable enough to provide a candidate for a novel dosimetry system.

An analyzer called “Q-chanG4” was developed with Visual Basic for photoluminescence quenching in a solid. This software can analyze the quenching mechanism in a solid matrix using emission decay curves and Stern-Volmer plots. Photoluminescence quenching of Tris(2,2’-bipyridine)ruthenium(II) in a polyethylene glycol solid by methylviologen was analyzed with Q-chanG4. The quenching mechanism was determined as a combination of a dynamic quenching and a static quenching involving multi-step equilibria and dynamic quenching. The dynamic quenching rate constant in the polyethylene glycol was as large as that in an aqueous solution, suggesting that the diffusion coefficient of molecules in the polyethylene glycol is almost the same as that in an aqueous solution in spite of the solid state.

水素原子の原子軌道をマルチメディア技術（静止画および動画）を用いて種々の表示方法（等値曲面, 擬三次元, 等高線, 断面図）で可視化するとともに, 対応する力学的振動についても同様に可視化した. 可視化結果を, CD-R (Compact Disk Recordable) に格納した. ランダム呼び出し可能な媒体の機能を使用して, 可視化データを任意に組合せて表示して対比させることにより, 節（節面）などの波の特徴を認識し, 原子軌道の波動性の理解を深めるよう工夫した.

A virtual bipolar photogalvanic cell was developed using Visual Basic. On the basis of the simulation, it is indicated that the charge separation (kd) and the charge recombination (kr) rate constants can be estimated using the photocurrent response. The thickness of the charge separation region can be anticipated by photocurrent response at various layer thicknesses. The increase in diffusion coefficients raises the short-circuit photocurrent to enhance the performance of the photogalvanic cell. An actual device was fabricated using tris(bipyridine)ruthenium(II) complex ([Ru(bpy)3]) as a sensitizer and Prussian Blue as a mediator. This device worked as a photogalvanic cell: short-circuit photocurrent (JSC), 2.3μA/cm2; open-circuit photovoltage (VOC), 0.118V; fill-factor, 20.5 %. It was shown from the action spectrum that electrons are transferred from [Ru(bpy)3] to Prussian Blue. The charge separation and the recombination rate constants were estimated, using the virtual device, to be 5 102 mol-1cm3s-1 and 6 109 mol-1cm3s-1, respectively.

A program written in JAVA language was developed for the virtual electrochemical measurement of a modified electrode with a finite diffusion thickness, e.g., an electrode coated with polymer film in which functional molecules were dispersed. This program, called ES-2, can simulate cyclic voltammetry and potential-step chronoamperospectrometry by considering the rate of charge injection from the electrode to the functional molecule and the diffusion of charge. The results are shown by a voltammogram (I-V curve), and concentration distribution in the layer at a series of voltages at cyclic voltammogram mode, I-t curve, and time dependence of concentration distribution in the layer at potential step mode and a text of current values, the fraction of the oxidized molecules (RCT ) and parameters used for the simulation in both modes. A dynamic textbook of electrochemistry can be constructed by this program combined with HTML text.

A program, called PLEC-1, has been developed with Visual Basic to simulate and analyze the electrochemical measurement of a polymer-coated electrode with dispersed functional molecules. The program has two independent buffers for oxidant and reductant per one material and can concurrently treat seven materials and three chemical reactions of either first- or second-order. The user can not only experience virtual cyclic voltammetry and potential-step chronoamperometry but also analyze cyclic voltammograms by the Gauss-Newton method using the program. In PLEC-1, simultaneous partial differential equations are solved by the combination of Crank-Nicolson and iteration methods.

5, 8-Diphenyl-5, 8-dihydroanthra[1, 9-bc:4, 10-b′c′]diquinoline (ADQ, 3) and its endoperoxide (ADQepo, 4) were photochromic compounds with high heat stability. By heating above 100°C, colorless ADQepo (4) was slowly converted to green ADQ (3) in toluene. Reaction of ADQepo with some protic acid gave ADQ (3) at room temperature. The mechanism of this reaction was proposed based on the measurement of electronic spectrum.

Electrochemical measurements in a three electrode system under finite conditions, e.g., at an electrode coated with a polymer film incorporating functional molecules have been simulated using a program written in the JAVA language. The simulation with or without a catalytic reaction by the functional molecules has been performed using the program. The shape of a cyclic voltammogram under finite conditions is different from that under infinite conditions applied to ordinary solution electrochemistry. The fraction of the functional molecules that accepted charges (RCT) has been calculated by integrating a concentration distribution. The current under finite conditions in a potential-step measurement deviated from that under infinite conditions above RCT ≈ 0.5. The program was introduced to a document on the electrochemistry written in HTML. It can be used by many students in an electrochemistry class without heavy loads on the server computer.

QTVR (QuickTime Virtual Reality) と呼ばれるソフトウェアを利用して，水素原子の原子軌道 19 種について対話型動画表示を実現させた．この動画表示が，量子化学の教育にどのように役立つか調査した．対話型動画の利用は，軌道の形状と数式の関係，節の形状と数式の関係を理解する手助けとなることがわかった．

The sensitivities to γ rays were investigated for photo acid generators: N-sulfonyloxy phthalimide 2, N-sulfonyloxy succinimide 3, N-sulfonyloxy 1, 8-naphthalimide 4, N-tosyloxy 5-norbomene-2, 3-dicarboximide 5, triphenylsulfonium trifluoromethane-sulfonate 6, diphenyliodonium chloride 7 and chloroform 8. The acid generation efficiency was monitored by the use of acid sensitive dye, fluoran dye 1a. The efficiency for γ irradiation decreased in the order 7>2>6>5>3>4. In the case of 8, decomposition of 1a was accompanied. 7 and 8 were of no practical use because volatile hydrogen chloride was generated. The others (2-6) generate methanesulfonic acid, p-toluenesulfonic acid or trifluoromethanesulfonic acid which are not so volatile acid as hydrogen chloride. N-sulfonyloxy imide compounds (2-5) have an advantage for practical use as dosimeter because these reagents dissolve in either polar or nonpolar solvent.

原子軌道関数は, r, θ, φを極座標とするとき, 原子核からの距離rのみに依存する動径部分Rn,l(r)と,角部分Yl,m(θ, φ)の積で表される．角度θ, φのみに依存する角部分は, 球面調和関数としてYl,m(θ, φ)= Θl,m(θ)Φm(φ).の式で表わすことができる．角部分には, 波動関数の対称性に関する情報が全て含まれるため, 重要である．われわれは, AVS (Application Visualization System)というソフトウェアの等値曲面表示技術を用いて，原子軌道の角部分の数式を可視化する新しい方法を研究した. 本方法では, Yl,m(θ, φ)・rはデカルト座標の[(x, y, z)系]に変換可能であることに注目し, Yl,m(θ, φ) /r(x, y, z)の値を, 40×40×40の格子点に対して求めて, その等値曲面を描くことで,角部分表示を実現する．本研究では, Y0,0(θ, φ), Y1,0(θ, φ), Y1,±1(θ, φ), Y2,0(θ, φ), Y2,±1(θ, φ), Y2,±2(θ, φ)について,３次元の角部分の数式を可視化し, これまでと同等の表示が得られることを確認した．また, 本方法は４次元を超える原子軌道の角部分の可視化にも適用でき, 拡張性が高いことを確認した．

Reaction of fluoran dyes 1a-1f with hydrochloric acid was investigated. Hydrochloric acid was added to the fluoran solution ([1a-1f]=1.0x10-4mol dm-3) in organic solvents, and absorbance of formed colored species 2a-2f was measured by UV-Vis Spectrometer. The increment of the electron donation ability of substituent X at 3-position of 1 resulted in the increase of the formation of 2. When the chloroform solution of the most sensitive compound 1a was irradiated with γ rays, the solution turned red even at dose of 1 Gy. In order to investigate the effect of acid generators, 1b was irradiated with γ rays. Tosyl chloride 4 showed the possibility as an applicant for dosimetry in place of diphenyliodonium chloride 5.

QTVR (QuickTime Virtual Reality) と呼ばれるソフトウェアを利用して，水素原子の原子軌道の新しい動画表示を行なった．これは，前もって種々の縮尺に相当する原子軌道を描画しておいて連続表示する方法である．この手法によれば，原子軌道の外側から近づいて原子軌道の内側に入っていくかのような効果，すなわち，仮想現実感が得られ，複数の球状の等値曲面を持つ 2s 以上の s 軌道や，複数の球状の節を持つ 5d3z2-r2 軌道などの等値曲面表示に有効であった．

This article is concerned with our recent achievement in developing synthetic chromogenic receptors for optical active amines and amino acid derivatives. Pre-organized (S)-1,1′-bi-2-naphthyl- and bis(indophenol)-derived calix[4]crown 1a shows naked-eye detectable chiral recognition between those enantiomers. The spectroscopic properties are reported, as well as an estimation of the enantioselectivity using an HPLC equipped with a chiral packing column.

Electrocatalytic CO2 reduction was studied by using a modified graphite electrode coated with cobalt octabutoxyphthalocyanine (CoPc(BuO)8) and dipped in an aqueous electrolyte. The CoPc(BuO)8 worked as a catalyst to produce CO with higher activity and selectivity than the non-substituted CoPc. Under typical conditions at pH 4.4, the most active and selective CO2 reduction was achieved at −1.30 V with turnover number of the catalyst ∼ 1.1 × 106 h−1 and the selectivity of the produced CO H 2 ∼ 4.2 . The high activity was ascribed to the electron-donating BuO substituents of the complex, which would facilitate the coordination of CO2 as well as the electron transfer from the complex to the coordinated CO2 molecule. The use of a poly(4-vinylpyridine) membrane to disperse the complex decreased the activity. The mechanism was investigated by the use of in situ potential-step chronoamperospectroscopy (PSCAS) in a homogeneous CoPc(BuO)8/pyridine solution. In the absence of CO2, distinct two-steps visible spectral changes were observed following the first and second reductions of the complex. However, under CO2 atmosphere, only the one-electron reduced species was present under steady state. It was proposed that the third reduction of a CO2-coordinated CoPc(BuO)8 should take place for CO production.

Applying the procedure of precise Pariser-Parr-Pople molecular orbital (PPP MO) calculations, in which a novel two center electron repulsion integral new-γ was used and spectrochemical softness parameter in the new-γ was evaluated based on the spectroactive aromatic sextet resonance system (ASRS) of a molecule, the wavelengths of the p-band of acenes and their higher analogues were predicted. The relationship between the annellation and the shift of the wavelength of the p-band was revealed. The guideline to design PAHs which possess the long absorption wavelengths was proposed.

Schrodingerの波動方程式の解の数式から原子軌道の三次元的な形を連想することは必ずしも容易ではない.本論文では, EGWS (Engineering Graphic Workstation) IRIS INDIGO XS24 (またはTITAN 3000) 上で, ソフトウェアAVS (Application Visualization System) を使って, 一連の水素原子軌道関数の三次元等値曲面を可視化したので報告したい.これらの図から, 軌道胞の数と原子軌道の節面の数の間の法則を視覚的に明らかにできることがわかった.

芳香族化合物への一重項酸素の付加反応は, ホトクロミックへの応用から極めて興味深い. しかし, 化合物によっては酸素の付加位置を特定することは難しい.アントラ[1,9-b,c:4,10-b';c]ジクロメン (1) の酸素付加体の単結晶を作成し, X線結晶構造解析によって酸素の付加位置を特定した.その結果は, AM1とPM3法によるHOMOの係数からの予測とも一致した.

スペクトルやクロマトグラムの各ピークの相互情報量を算出し、ピークの重要度を示す尺度として利用した。大気汚染物質を測定したガスクロマトグラムに相互情報量を適応したところ、大きな相互情報量を持つピークは化学的にも重要なピークであることが分かった。すなわちピーク情報量は、膨大なデータ中から注目すべき重要な部分を抽出する尺度として利用できる。さらに測定データを構成する事象毎にピーク情報量を分割することで、ピークの帰属にも利用できることが分かった。

著者らは, 先にホトクロミズムを示す縮合多環芳香族化合物であるベンゾ [1, 2, 3-kl : 4, 5, 6-k'l'] ジキサンテン (1a) の硫黄類似体 (1b) および, そのエンドペルオキシド体 (2b) を合成し, ホトクロミック特性を測定して報告を行った.その中で, (2b) は (1a) の消色型化合物 (2a) と比較して, 着色体を再生する相対反応速度が著しく小さいことが分った.この実験事実を, 計算化学の手法を用いて得られた, (1a) のキサンテン環同士のなす二面角, (1b) のチオキサンテン環同士のなす二面角の差をもとに説明を試みた.

Fluorescence emission spectra are reported for naphth[2′l′8′7′: 4,10,5]anthra[l,9,8cdef]cinnoline, benzo[lmn][3,8]phenanthroline (also called 2,7-diazapyrene), benz[4,10]anthra[l,9,8cdef]cinnoline, naphtho[8,1,2hij]pyreno[9,10,ldef]phthalazine, acenaphtho[l,2b]pyridine, benzo[a]phenazine, indeno[l,2,3ij][2,7]naphthyridine, and indeno-[l,2,3ij]isoquinoline dissolved in organic nonelectrolyte solvents of varying polarity and acidity. Results of these measurements indicate that naphth[2′,1′,8′,7′:4,10,5]anthra[l,9,8cdef]cinnoline exhibits some signs of probe character as evidenced by changing emission intensity ratios; however, numerical values did not vary systematically with solvent polarity. The effect of nitromethane and 1,2,4-trimethoxybenzene as selective quenching agents on both the unprotonated and protonated PANHs was also examined. Nitromethane was found to quench fluorescence emission of roughly two-thirds of the alternant unprotonated PANHs studied to date. Emission intensities of the protonated PANHs remained essentially constant and were not affected by nitromethane. 1,2,4-Trimethoxybenzene, on the other hand, quenched the fluorescence emission of several unprotonated and all protonated PANHs examined.

Nitromethane is examined as a selective fluorescence quenching agent for alternant polycyclic aromatic nitrogen hetero-atoms (PANHs). Fluorescence emission behavior is reported for 1-azapyrene, 2-azapyrene, 4-azapyrene, 4-azachrysene, 12-azabenzo[a]pyrene, phenanthro[9, 10g]isoquinoline, phenanthro[2,3h]isoquinoline, phenanthro[3,2h]-isoquinoline, 2-azabenz[a]anthracene, 1-azabenz[a]anthracene, 9-azabenz[a]anthracene, dibenzo[c,i]phenanthro[1,10,9,8anmlk]phenanthridine, diphenanthro[9,10,1def;1',10',9'hij]phthalazine, and benz[de]isoquino[1,8gh]quinoline dissolved in acetonitrile or aqueous-acetonitrile solvent mixtures at various nitromethane concentrations. Results of these measurements show that nitromethane does quench fluorescence emission of ten of the solutes studied; however, phenanthro-[2,3h]isoquinoline, 9-azabenz[a]anthracene, benz[de]isoquino[1,8gh]-quinoline, and dibenzo[c,i]phenanthro[1,10,9,8anmlk]phenanthridine are notable exceptions.

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.

The applicability of semi-empirical PPP and INDO/S molecular orbital calculations For indoanilines (3) was investigated under three structural points of view: syn/anti isomerization, resonance canonical structures, and non-planarity of the molecule.

By taking a birds-eye view from the n-dimensional world (or n-space), it was found that thež conventionally used sp, sp2, and sp3 hybridized atomic orbitals belong to the spn hybridization and their geometrical shapes correspond to n-simplexes, which are, respectively, the smallest geometrical objects in n-space. Similarly, sp, sp2d, and sp2d3 hybridizations are found to belong to the spndn–1 hybridization, whose geometrical shapes correspond to n-cross polytopes (obtained from 2n vertices equidistantly located on n rectangular coordinate axes). Another series of n-cube hybridization is also discussed, whose 3-space member is 8-coordinated cubic hybridization, sp3d3f. General analytical forms of the wavefunctions of these three series of hybridized atomic orbitals in n-space are obtained. The periodic table and related problems of atoms and molecules in n-space are discussed.