Showing papers in "Bulletin of the Chemical Society of Japan in 1961"

The Surface Tension and the Critical Micelle Concentration in Aqueous Solution of β-D-Alkyl Glucosides and their Mixtures

Abstract: The surface tension in aqueous solutions of β-D-alkyl glucoside and their mixtures at 25°C has been measured. The CMC was determined from the inflexions of the curves; octyl glucoside, 0.025 mol./1., decyl glucoside 0.0022 mol./1., dodecyl glucoside, 0.00019 mol./1. The effect of hydrocarbon chain length was explained theoretically. The CMC of mixtures has been also explained by the extension of the theory of ionic agents. The effect of added sodium chloride, calcium chloride and sodium sulfate on the surface tension in aqueous solution of octyl glucoside has been measured. The effect of added salts on the CMC was determined from the inflexions of the surface tension vs. logarithm of concentration curves.

Infrared Spectra of Water of Crystallization in Some Inorganic Chlorides and Sulfates

Abstract: The characteristic bands of water of crystallization in various chlorides and sulfates were determined in the rock salt region. The results were classified and explained inclusively by the effects of coordination and hydrogen bonding.

Ultraviolet Spectra of N -Heterocyclic Systems. I. The Anions of Uracils

Abstract: In aqueous solutions uracil exists predominantly in the diketo form, whereas in alkaline solutions it exists as an approximately 1:1 mixture of two deprotonated forms. The two deprotonated anions show ultraviolet absorptions similar to the anions of 1-methyluracil and 3-methyluracil, and the main contributing canonical structures which give rise to the general absorption feature of the anions are discussed. The peak shifts accompanying N-alkylation or deprotonation may be summarized in a simple empirical rule. Individual ionization constants have also been estimated. The results of uracil can be extended to thymine, uridine, thymidine, and their phosphates. The pesent method can probably be extended to other systems containing two dissociable protons.

Infrared Absorption Spectra of Quartz and Some other Silica Modification

Abstract: Some silica modification such as carplex and ground quartz particle, gives rise to the bands near 950 cm−1. This band has no relation with the skeletal structure of Si–O bond and can not be explained as overtone or combination tone. It is reasonable to assign this band to O–H deformation vibration of silanol group. The effect of particle size and grinding time on the spectrum of quartz was examined and it was concluded that the ground quartz particle was covered by some irregular structure on its surface, which was different from quartz structure. In this surface structure, the silanol group seems to be constructed.

Electronic Spectra of Substituted Aromatic Hydrocarbons. II. Naphthols and Naphthylamines

Abstract: The ultraviolet absorption spectra of α-, β-naphthols and α-, β-naphthylamines have been newly measured down to 200 mμ. On the basis of a calculation which was carried out in the same manner as in the preceding paper, the effect of substitutions at α- and β-positions upon the spectrum of napthalene has been explained and the assignment of the observed absorption bands has been made. It is suggested that, upon substitution at the α-position, the Au→B3u+ band of naphthalene splits into two electronic bands because of the interaction of the B3u+ state with a B1g+ state. Molecular diagrams are given for naphthylamines and for aniline.

Acid-Base Property and Metal Chelate Formation of 4-(2-Pyridylazo)-resorcinol

Abstract: Acid dissociation stages of analytical reagent 4-(2-pyridylazo)-resorcinol (PAR) and metal chelate formation of PAR were investigated by absorption measurements and pH-titrations. The first acid dissociation constant was determined as 1.48×10−6 (pka1=5.83) and the second as 3.2×10−13 (pka2=12.5) at 25°C. PAR forms 1 : 2 chelate with Fe(III), Co(II) and Ni(II), and forms 1:1 chelate with Cu(II), Zn(II), Cd(II), Hg(II) and Pb(II). The stability constant of copper(II)-PAR chelate was determined as 5×1011 at 25°C. Some analytical aspects of PAR were also discussed.

Electronic Spectra of Substituted Aromatic Hydrocarbons. I. Phenol and Aniline

Abstract: The electronic spectra of monosubstituted benzenes are examined from the viewpoint of semi-empirical MO theory. To allow for electronic interaction, the simple LCAO method is refined in the light of purely theoretical procedure, configuration interaction being included. The refined method is particularly convenient for dealing with the spectra of substituted organic compounds. The origins of the absorption bands for phenol and aniline are clarified on the basis of the calculated excitation energies, oscillator strengths and changes of charge distribution accompanying electronic transitions. The nature of the second excited state of aniline is discussed in detail, in connection with the problem of electron transfer.

A Simplified Model for the Structure of Water

Abstract: Various characteristic properties of liquid water can be explained fairly well by a simple structural model proposing that water consists of an equilibrating mixture between two states: the icy state which possesses ice structure and appears and disappears locally and temporarily, and the packed state in which water molecules are closely packed without hydrogen bondings. Only assuming that the fraction of the icy state at 100°C is 0.2, the fractions and the equilibrium constants at various temperatures are calculated, and therefrom the heat and the entropy of fusion of ice, the specific heat and the heat of vaporization of liquid water are derived, which are all in good agreement with the observed values. The radial distribution function of water obtained by X-rays reveals the packed state to have a structure similar to the closest packing, and the surface tension of water tells that the surface of water is more abundant in the icy state than the bulk water is, positively adsorbed as if it were a kind of ...

Infrared Spectra of Acyclic Imides. I. Two Modifications of Diacetamide in the Crystalline State

Abstract: Two crystal forms have been found for diacetamide (the form A and the form B). Infrared spectra of these two forms of diacetamide and diacetamide-d have been measured in the region 3600 to 400 cm−1 and many differences of absorption bands have been observed. It has been shown that these differences of absorption bands can be explained to result from rotational isomerism. The trans-trans planar structure of the –CONHCO–group has been proposed to correspond approximately to the molecular structure of the unstable form (the form B) of diacetamide. The frequency shifts of absorption bands on deuteration in the potassium bromide region has been discussed to give support to this interpretation. An assignment has been given to each absorption band in the potassium bromide region for the form A and the form B of diacetamide and diacetamide-d.

Distribution of Various Elements between Nitric Acid and Anion Exchange Resin

Abstract: Distribution coefficient of some metallic elements between nitric acid and anion exchange resin were measured. From the results described above, the fundamental data on the separation of each element in nitric acid were obtained.

Organic Semiconductors with High Conductivity. III. Perylene-Iodine Complex

Abstract: Concerning the solid complex of perylene-iodine system, it has been clarified that two sorts of molecular addition compounds are formed. One has the composition of Perylene· 1.5 I2 (or 2 Perylene· 3 I2) and the other is Perylene· 3 I2. Both complexes are semiconductive with low resistivity; the resistivity at the room temperature is 9∼10 ohm.cm. and the energy gap is 0.06 eV. Concerning those values, both complexes possess almost the same values. Not only the elecrical properties and the magnetic properties, but also, both complexes possess similar crystal structures. To explain those facts, the structural units for those complexes have been proposed. These consist of the conjugation between perylene molecules and iodine molecules with the charge tranfer type of interaction.

Synthesis and Physical Properties of Normal Higher Primary Alcohols. IV. Thermal and X-Ray Studies on the Polymorphism of the Alcohols of Even Carbon Numbers from Dodecanol to Tetratriacontanol

Abstract: 1. Determination of the melting points and transition points of the even carbon numbered alcohols from C12 to C34 was made by thermal analysis. The transition points of the alcohols above C18, except C22, have never been reported. 2. The reversible transition sets in at C14 and terminates at C26. The transition of C28 and C32 is irreversible, appearing only on cooling and both transitions disappear at C34. Probably the pure sample of dodecanol may indicate no transition in any methods of measurements. 3. Properties of the a forms gradually change with increasing chain lengths. 4. The β to γ and α to γ transformations were examined by X-ray pattern measurements and the results were discussed. 5. Transition points and X-ray spacings may be reliable criteria of purity of higher alcohols, and probably of some other long chain compounds.

Infrared Absorption Spectra of Water of Crystallization in Copper Sulfate Penta- and Monohydrate Crystals

Abstract: The observed spectra of water in the penta-and monohydrate crystals were interpreted by the effects of coordination copper-water and hydrogen bonding O-H…O. The whole difference in the spectra of the two crystals were explained in relation to the escape of the four ligand water molecules and the resulting rearrangement of atoms. The stretching, bending and rocking modes, which are single in the case of the pentahydrate, split into doublets in the monohydrate. This result was explained by a single assumption of strong coupling of two neighboring water molecules in the latter.

Silanes. Vibrational Assignments and Frequency Correlations

Abstract: The status of knowledge relative to the vibrational assignments, molecular structure, and spectral data for a series of about one hundred silanes has been surveyed and is reported in brief tabular form. A scheme of simplified vibrational modes is discussed, and used to develop the assignment of fundamentals for some fifty five silanes. Some new assignments are proposed in the light of a correlation rule which has been developed. Tables of characteristic frequencies, and the best values for bond distances, based on this work, are presented.