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Structural analysis of high density H(D) absorbed Pd particles with 5 nm dispersed ZrO2 has been carried out using XAFS (X-ray Absorption Fine Structure) techniques. X-ray absorption spectra around the Pd K-absorption edge were observed and analyzed. The Pd–Pd bonding distance was enlarged by 0.08 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. The hydrogen absorption mechanism will also be discussed.

Structural changes in Li 1− y Ni 0.5 Mn 0.5 O 2 with Li de-intercalation were studied using X-ray diffraction, XAFS, and magnetic measurements. The Li de-intercalation from LiNi 0.5 Mn 0.5 O 2 proceed mainly by a valence state change of Ni ions from Ni 2+ to Ni 3+ up to y =0.5 from the XANES and magnetic results. Structural analysis clarified that a second order phase transition from trigonal to monoclinic was observed between y =0.2 and 0.3 and that a small fraction of the Li ions start to migrate from the octahedral 2 a site to the tetrahedral 4 i site at y =0.3 and most of the Li ions occupied the tetrahedral 4 i site at y =0.5 with Li de-intercalation. The EXAFS analysis clarified the valence state change and the range of phase transition during the Li de-intercalation, from the changes in the bond distance of the first neighbor for each transition metal. This Li de-intercalation mechanism is characteristic of this system and has not been reported for Li 1− y MO 2 (M=Co and Ni).

The cell performance of Li1-xNi0.5Mn0.5O2 Using Li exhibited a specific capacity of c.a. 150 mAh/g in the voltage range of 2.5 to 4.3 V. XRD and XAFS measurements using synchrotron radiation were carried out to observe the average and the local structural changes during a charging process. As the cell charged, Ni K-edge of XANES spectra showed the chemical shift towards higher energy in the voltage range of 2.5-4.1 V and then no remarkable shift up to 4.3 V. It was found that nickel of x=0 in Li1-xNi0.5Mn0.5O2 was located in divalent and manganese in tetravalent at the octahedral site. Lithium was removed by the oxidation of Ni, resulting in the ordering of cations in the layer, that is, appearance of the monoclinic phase at x=0.5.

The substitution of Li+ for Zn2+ and Ti4+ for Fe3+ in ZnFe2O4 with the spinel stype structure was adopted to obtain the fundamental understanding of the Li ion conduction in solids. The cation distribution of the compound was investigated at the starting research. The XRD patterns indicated the formation of the solid solution, Zn1-xLixFe2-xTixO4 and the lattice parameter decreased linearly with the increase of x in accordance with the ionic radius for each cation. Above x = 0.6 a slight curvature appeared in the composition dependence of the lattice parameter. The Rietveld analysis determined the cation distribution for the present system. It can be written as Zn1-xFex[8a][Lix/2Fe1-xTix/2][16d]2O4 (for x 0.5). The observed change in the composition dependence of the lattice parameter is caused by the change of the cation distribution in the spinel structure. In addition, the iron distribution for the present system was confirmed by the Mossbauer spectroscopy. The electrochemical lithium insertion was also discussed.

In the course of searching for oxide ion conductors, perovskite oxides were synthesized by use of the conventional solid state reaction. The basic composition is Sr 4 In 2 Zr 2 O 11 , and the phase obtained shows a cubic perovskite structure indicating that the oxygen vacancies are disordered in this phase. The electrical conductivity of this material was estimated from ac impedance measurement, in the absence of the measurement of ionic transference number, and it was found to show the conductivity of 0.02 S cm −1 at 1273 K. The conductivity was depressed by the substitution of Ga 3+ for In 3+ and Y 3+ for Zr 4+ .

The high-temperature crystal structure of Sc 2 O 3 -doped ZrO 2 (ScSZ) was investigated by in situ neutron powder diffraction and XAFS measurements. The former revealed an oxygen displacement along [111] and the latter a distortion in the surrounding neighbors at high temperatures. High ionic conduction in ScSZ is examined in terms of crystal structure.

Cysteamine was condensed with glyoxylic acid monohydrate in a mixture of acetic acid and ethanol in the presence of (2R, 3R)- or (2S, 3S)-tartaric acid [(R)- or (S)-TA], as the resolving agent, to give the salt of (-)-2-thia-zolidinecarboxylic acid [(-)-2-THC] with (R)-TA or the salt of (+)-2-THC with (S)-TA. Treatment of these salts with triethylamine in methanol afforded (-)- and (+)-2-THC. The (-)- and (+)-2-THC obtained were betermined to be enantiopure forms by comparing their powder X-ray diffiraction patterns with that of (RS)-2-THC. The absolute configurations of (-)- and (+)-2-THC were estimated based on molar rotations of (2R, 4R)- and (2S, 4S)-2, 4-thiazolidinedicarboxylic acids, (R)-4-thiazolidinecarboxylic acid, and (-)- and (+)-2-THC. (-)-2-THC was determined to have the (R)-configuration, and (+)-2-THC to have the (S)-configuration.

Structural analysis of high Deuterium absorbed 5 nm Pd particles in dispersed ZrO2 has been carried out using XAFS techniques. X‐ray absorption spectra around the Pd K‐absorption edge were observed and analyzed. The Pd–Pd bonding distance in the fcc Pd lattice was enlarged by 0.08 ∼ 0.09 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. XANES spectra clearly indicate that any change in the oxidation state of Pd are not observed, resulting in no reaction of the absorbed Deuterium atoms with Pd atoms. This paper reports the alternation of Pd lattice in nano‐sized composite during hydrogen absorption. The possible models of deuterium position in the Pd lattice are also discussed.

Five metabolites tentatively called GS-1 (1)-5 (5) from Gelasinospora santi-florii, and four tentatively called EQ-4 (6), EQ-6 (7)-8 (9) together with 1-4 from Emericella quadrilineata have been isolated in a screening study on immunomodulatory fungal constituents. Among these nine metabolites, EQ-7 and 8 have been unknown. This time, the structures of GS-4 which has previously been isolated, EQ-7, and -8 have been determined to be (4R,4aS,9aR)-1,9a-dihydronidulalin A (4), (4S,4aR,9aR)-4a-carbomethoxy-1,4,4a,9a-tetrahydro-4,8-dihydroxy-6-methylxanthone (8), and 9-hydroxymicroperfuranone (9), respectively, and the six other metabolites have been identified. On bioassay, a dihydroxanthone, nidulalin A (1), a hexaketide, sordarial (5), and a xanthone, pinselin (7) have displayed significant immunosuppressive activities. The structure-activity relationships of these constituents have also been discussed.

Synchrotron X-ray diffraction and XAFS measurement have been employed to investigate structural change and the charging process of a layered LiNi0.5Mn0.5O2 cathode material. The structure of charged Li1−xNi0.5Mn0.5O2 (x=0.5), which corresponds to the composition for showing rechargeable capacity, was determined. The results showed that divalent nickel metal was oxidized to trivalent after charging, in association with the phase transition from hexagonal (R3-m) to monoclinic (C2/m) resulting from the ordering of cations in the layered structure.

The structural change and charging process for Li1−xNi0.5Mn0.5O2 were determined by x-ray diffraction and XAFS measurement. XAFS has been employed to investigate the change in electronic structure of cathode material. As the cell charged, the Ni K-edge XANES spectra showed chemical shift towards higher energy, while Mn K-edge showed no significant shift. Divalent nickel metal is oxidized to trivalent with Li-deintercalation, in association with the phase transition from hexagonal (R3m) to monoclinic (C2/m).

The effects on the electrical conductivity and the crystalline structure of the addition of HfO 2 , CeO 2 , and Ga 2 O 3 to ZrO 2 with 11 mol % Sc 2 O 3 (11 ScSZ) have been examined. 11 ScSZ has the rhombohedral structure and is transformed to cubic structure at 580°C. The cubic phase was stabilized at room temperature by the addition of about 6 mol % CeO 2 , and 2 mol % Ga 2 O 3 to 11 ScSZ. No such effect was observed by addition of HfO 2 . The electrical conductivity of 11 SCSZ was depressed by the addition of HfO 2 , CeO 2 , and Ga 2 O 3 .

The effects of the surface properties of alumina upon the conductivity enhancement in the LiIAl 2 O 3 composite were studied by means of a thickness of the interfacial layer. Neither the surface area measured by the BET method nor the particle size showed any correlation with the thickness. Heat-treatment of alumina resulted in a slight decrease of the thickness. Among the surface properties changed with this treatment, the amount of basic active sites, especially the -OH group, is the most plausible species to have an effect on the conductivity enhancement.

A composite solid electrolyte of the LiBr·H 2 OAl 2 O 3 system was studied by means of the 7 Li spin-lattice relaxation time. Two kinds of Li were observed in it; one of them has the same T 1 values as pure LiBr·H 2 O with an activation energy of 52 kJ mol −1 for the Li + -ion self diffusion. The other showed a different temperature behaviour from LiBr·H 2 O with respect to the phase transitions, suggesting formation of a new compound in the composite electrolyte. Judging from its activation energy of 18 kJ mol −1 , this compound should be responsible for the enhancement of the ionic conductivity. The thickness of the highly conductive layer was estimated from a ratio of the NMR signal intensity applied to the preconceived model. Its composition dependence explains the composition dependence of the enhancement effect.

Diffusion of a Li atom in an anode material β-LiAl was studied over the composition range of 48.0–50.2 at % Li by the 7 Li magnetic relaxation times. Dependence of T 1 upon temperature and the resonance frequency was successfully explained by a vacancy diffusion on the Li sublattice involving a distribution of the activation energy for migration, E a . The central value of E a was almost independent of the composition (⋍ 13.8 kJ mol -1 ), while the width of distribution increased with increase of the number of substituted Li on the Al sublattice. The obtained diffusion constants, extrapolated to 415°C, were larger by a factor of 1.8–3.4 than those obtained by the electrochemical method.

The magnetic susceptibilities, χ, of α- and β-Cu(NH3)2X2(X=Cl, Br) were measured from 4.2 to 360 K. Those of β-Cu(NH3)2X2 obeyed the Curie-Weiss law above 50 K. The Weiss constants and effective Bohr magneton numbers are −3.5(±1) K and 1.75(±0.01) for X=Cl, and −9.7 K and 1.82 for X=Br. α-Cu(NH3)2Cl2 showed a rounded maximum for χ at 30 K. A linear Heisenberg model with the parameters, J=−23.5(±1) K and g=2.03(±0.03), gave good agreement with observations. α-Cu(NH3)2Br2 had a peak for χ at 47(±2) K. This temperature is probably a Neel temperature. The strong magnetic interaction of the α-form compounds is related to the compressed coordination octahedron of [Cu(NH3)2X4]2−. All samples used were solid solutions of Cu(NH3)2X2 and NH4X. An analysis of χ suggests that the Cu2+ cations in α-Cu(NH3)2Cl2 are distributed inhomogeneously over a short range. A similar inhomogeneity was also found for the β-Cu(NH3)2X2 samples. In this sense, the β-form may be better described as a solid solution of α-Cu(NH3)2X2 and ...

Charge transport properties of β-LiAl were studied in the composition range of 48.0–50.2 at.% Li. Measurements were made on single crystal samples and down to the liquid He temperature. The resistivity changes linearly with temperature above 125 K, with a thermal coefficient of 72–95nΩ cm K−1. The Matthiessen law was obeyed very well. A component dependent on temperature, which was described by the Gruneisen formula, is insensitive to a change of the chemical composition. On the other hand, the residual resistivity depends largely on the composition and contributes up to 58% of the total resistivity in Li0.498. It is chiefly due to the substituted Li atoms on the Al sublattice.

Magnetic susceptibilities, χ, of Cu2AsO4(OH), Cu2(OH)PO4, and Cu2OSO4 have been measured from 4.2 to 360 K to establish the role of the OH− and O2− ions in the magnetic superexchange interaction. The former two compounds showed a broad maximum for χ at 118 and 110 K, respectively. Although the crystal structure is three-dimensional, only a tetramer model with two parameters can explain the temperature dependence of χ, since the hydroxide anion causes a strong magnetic interaction which is limited to four copper atoms between which the anion is intermediary. The magnetic susceptibility of Cu2OSO4 obeyed the Curie-Weiss law above 140 K with a Weiss constant of −56 K. At 16 K the compound transformed into a ferrimagnetic phase, the effective megneton number of which is 0.11 at 4.2 K. A canted ferrimagnetic structure has been proposed and the canting angle estimated. In the superexchange interaction, only hydroxide and oxide anions are significant and both anions behave similarly.

Diffusive motion of a Li + ion in the solid solution of Li 3 +x(P 1 −x, Si x )O 4 (0⩽ x ⩽0.4) with the γ II -Li 3 PO 4 structure was studied by the measurement of the 7 Li spin-lattice relaxation time. The observed motion was a local motion instead of a long-range one. In comparison with the previous study on the solid solution of Li 4 −x(P x , Si 1 −x)O 4 with the Li 4 SiO 4 structure, it is noticeable that the activation energy is low and almost independent of the composition and that the attempt frequency is smaller in this phase. These characteristics were attributed to the availability of a large interstitial void in the γ II -Li 3 PO 4 structure. The low values of activation energy for the Li + ionic conduction may be explained on the same basis.

Both ionic conductivity and 7 Li NMR relaxation time T 2 were studied on Li 3 N single crystal samples containing an oxygen impurity. Owing to the O impurity, the samples showed a high ionic conductivity (σ⊥ = 0.83 S m −1 and σ ∥ = 0.013 S m −1 at 300 K) and a low activation energy ( E a ,⊥ = 0.19 eV and E a ,∥ = 0.24 eV). The intrinsic conduction accompanying vacancy generation within the Li 2 N layer was observed in the high temperature region. In the extrinsic region only a motion of the Li ion located in the Li 2 N layer is responsible for both σ ⊥ and σ ∥ . The site exchange motion of two kinds of Li ion has little importance to the ionic conduction.

Effect of the surface modification of γ-Al 2 O 3 with an alkali or alkaline earth cation was studied in the composite solid electrolyte system of LiI  γ - Al 2 O 3 . The alumina surface was modified through adsorption of nitrate salts and subsequent thermal decomposition at 800°C. All the composite samples showed the enhancement of the conductivity. The degree of the enhancement was dependent on the modifier cation, ranging from 10 to 20, and was higher than that of the unmodified composite sample. Three types of the extrinsic conduction were distinguished from the activation energy near 100°C: 0.49, 0.36 and 0.28 eV. A good positive correlation was observed between the maximum conductivity and the pH of a suspension of the modified alumina, supporting the idea that the basic active sites on the alumina surface play an important role in the enhancement effect.

Occurrence of a highly conductive phase was confirmed by a 7Li NMR study in a composite solid electrolyte LiBr·H2O–Al2O3. Thickness of an interfacial layer on a dispersed alumina particle was estimated to be 0.2 μm for 3LiBr·H2O–2Al2O3. Changes of the relative intensity in an X-ray diffraction pattern were pointed out.

Self diffusion of Li + ions in Li x Ti 1+y S 2 ( x =0–1, y =0.01–0.11) has been studies by means of the 7 Li NMR relaxation time T 1ϱ . Li x Ti 1.01 S 2 , with an approximately stoichiometric Ti content, had a self diffusion coefficient of 2 × 10 −10 cm 2 s −1 at 25°C for x ≤ 0.8. On the other hand, samples with the composition deviated from the stoichiometry had lower self diffusion coefficients and higher activation energies. Excess Ti ions showed the pinning and blocking effects which inhibit the Li + -ion diffusion in the interlayer of TiS 2 .

Diffusion properties of Li ion in a cathode material of amorphous Li x V 2 O 5 with 5 mol% P 2 O 5 (x=0.2−2) were studied by means of 7 Li NMR. From the relaxation time, T 1ϱ , the diffusion coefficient at 25°C was obtained to be 4×10 −14 cm 2 s −1 for x=0.2 and 2.8×10 −12 cm 2 s −1 for x=2. Both pre-exponential factor, D 0 , and the activation energy, E a , of the diffusion coefficient decreased with the increase of x. From the second moment, Li + ions seemed to occupy sites approximately 2.9 A apart in a large cavity similar to that in the crystalline V 2 O 5 . It was suggested that there are three kinds of sites for the Li + ion in the cavity, and that the ion changes the site of one kind to the others at x ⋍0.6 .

Composite solid electrolyte of the LiIAl2O3 system was studied by means of the 7Li NMR relaxation time. Occurrence of a highly conductive phase in the composite was confirmed. Self diffusion constant of Li in this phase was 8.1×10−10 cm2 s−1 at 300 K. The value is 1600 times larger than that in the LiI matrix and of a reasonable order of magnitude to explain the enhanced conductivity quantitatively. Composition dependence of the enhancement could be explained by a change in thickness of the interfacial layer between an Al2O3 particle and the LiI matrix.

Magnetic, IR and electronic spectral studies were made on CuSeO3·2H2O, its crystal structure being refined. The IR band at 927 cm−1 was found to be due to a rocking vibration of a water molecule. The H-bonding scheme was suggested. The electronic spectrum shows a maximum of the d-d transition bands at ca. 14000 cm−1. This was explained on the basis of a square pyramidal coordination of a Cu ion. Above 100 K the magnetic susceptibility obeys the Curie-Weiss law with θ=−92·6 K and μeff=2.00βB. At lower temperatures it shows a broad maximum at ca. 45 K, a sharp peak at 26.4 K corresponding to TN. The behaviour could be explained from the antiferromagnetic superexchange interactions of Cu cations through the σ-bonds of SeO32− anions. The small anisotropy and the number of cations intermediated by each anion give rise to the 1-dimensional character. A linear Heisenberg model and the molecular field model gave J⁄k values of −33 and −31 K, respectively. The latter model also gave the observed ratio of |θ|⁄TN.

Hydrogen bronzes, HxV2O5, HxNb2O5, HxMoO3 and HxWO3, were synthesized by irradiating respective oxide powders, either with or without loading of Pt, suspended in 1 : 1 aqueous ethanol solution. All products had a different colour from the parent oxides, which fades out in a moist air. Photoacoustic spectra showed a broad and structureless absorption over the visible region. This method gives bronzes with a small x value (x ?? 0.02) except for H0.32V205 and having the same X-ray diffraction pattern as that of the parent oxide.

Diffusive motion of an Li+ion in the solid solution Li4−x(PO4)x(SiO4)1−x (0 ≦ x ≦ 0.35) was studied by 7Li pulsed nmr between − 70 and 440°C. Activation energies for an Li+ ion diffusion decreased monotonically with increasing x in the composition. These values are smaller than those reported from the measurement of ionic conductivity. Discrepency seems to result from the local nature of an Li+ diffusion observed by nmr contrary to the long-range one in the ionic conduction.

The crystal structure of sodium hexahydroxoantimonate (V), NaSb(OH)6, has been refined. The previous structure given by Schrewelius was confirmed, but the positional parameters of oxygen atoms were shifted significantly. Both antimony and sodium atoms are surrounded by six oxygen atoms octahedrally. The interatomic distances are: Sb–O=1.972–1.999 A (mean 1.98 A), O–O=2.758–2.834 A (2.80 A) for an SbO6 octahedron, Na–O=2.375–2.406 A (2.39 A) and O–O=3.229–3.526 A (3.38A) for an NaO6 octahedron. Two types of sequences of hydrogen bonds were recognized. They were compared with the sequences of hydrogen bonds in In(OH)3 and MnSn(OH)6.

The magnetic susceptibilities, χ, of α- and β-Cu(NH3)2X2(X=Cl, Br) were measured from 4.2 to 360 K. Those of β-Cu(NH3)2X2 obeyed the Curie-Weiss law above 50 K. The Weiss constants and effective Bohr magneton numbers are −3.5(±1) K and 1.75(±0.01) for X=Cl, and −9.7 K and 1.82 for X=Br. α-Cu(NH3)2Cl2 showed a rounded maximum for χ at 30 K. A linear Heisenberg model with the parameters, J=−23.5(±1) K and g=2.03(±0.03), gave good agreement with observations. α-Cu(NH3)2Br2 had a peak for χ at 47(±2) K. This temperature is probably a Neel temperature. The strong magnetic interaction of the α-form compounds is related to the compressed coordination octahedron of [Cu(NH3)2X4]2−. All samples used were solid solutions of Cu(NH3)2X2 and NH4X. An analysis of χ suggests that the Cu2+ cations in α-Cu(NH3)2Cl2 are distributed inhomogeneously over a short range. A similar inhomogeneity was also found for the β-Cu(NH3)2X2 samples. In this sense, the β-form may be better described as a solid solution of α-Cu(NH3)2X2 and ...

Magnetic susceptibilities, χ, of Cu2AsO4(OH), Cu2(OH)PO4, and Cu2OSO4 have been measured from 4.2 to 360 K to establish the role of the OH− and O2− ions in the magnetic superexchange interaction. The former two compounds showed a broad maximum for χ at 118 and 110 K, respectively. Although the crystal structure is three-dimensional, only a tetramer model with two parameters can explain the temperature dependence of χ, since the hydroxide anion causes a strong magnetic interaction which is limited to four copper atoms between which the anion is intermediary. The magnetic susceptibility of Cu2OSO4 obeyed the Curie-Weiss law above 140 K with a Weiss constant of −56 K. At 16 K the compound transformed into a ferrimagnetic phase, the effective megneton number of which is 0.11 at 4.2 K. A canted ferrimagnetic structure has been proposed and the canting angle estimated. In the superexchange interaction, only hydroxide and oxide anions are significant and both anions behave similarly.

Magnetic, IR and electronic spectral studies were made on CuSeO3·2H2O, its crystal structure being refined. The IR band at 927 cm−1 was found to be due to a rocking vibration of a water molecule. The H-bonding scheme was suggested. The electronic spectrum shows a maximum of the d-d transition bands at ca. 14000 cm−1. This was explained on the basis of a square pyramidal coordination of a Cu ion. Above 100 K the magnetic susceptibility obeys the Curie-Weiss law with θ=−92·6 K and μeff=2.00βB. At lower temperatures it shows a broad maximum at ca. 45 K, a sharp peak at 26.4 K corresponding to TN. The behaviour could be explained from the antiferromagnetic superexchange interactions of Cu cations through the σ-bonds of SeO32− anions. The small anisotropy and the number of cations intermediated by each anion give rise to the 1-dimensional character. A linear Heisenberg model and the molecular field model gave J⁄k values of −33 and −31 K, respectively. The latter model also gave the observed ratio of |θ|⁄TN.