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Heat capacities of a molecular mixed-ligand complex [Zn(hfac)2(tmen)] were measured in the temperature range between 13 and 383 K with an adiabatic calorimeter and the proton magnetic spin–lattice relaxation times (T1, T1ρ and T1D) were measured in the range between 130 and 330 K, where hfac and tmen denote hexafluoroacetylacetonato and N,N,N′,N′-tetramethylethylenediamine, respectively. The orientationally disordered crystalline phase, designated as phase I, was found to appear only in the supercooled meta-stable state: The temperature, enthalpy and entropy of the fusion were Tfus=(370±1) K, ΔfusH=(2.2±0.1) kJ mol−1 and ΔfusS=(5.8±0.3) J K−1 mol−1, respectively. The small entropy was discussed in relation to the low globularity in the shape of the complex molecule. High- and low-temperature stable crystalline phases (II and III) were found: The temperature, enthalpy and entropy of the fusion from the phase II were Tfus=(375±1) K, ΔfusH=(24.32±0.02) kJ mol−1 and ΔfusS=(65.4±0.1) J K−1 mol−1, respectively. The temperature, enthalpy and entropy of the III-to-II phase transition were Ttrs=(293.8±0.1) K, ΔtrsH=(4.115±0.005) kJ mol−1 and ΔtrsS=(14.02±0.02) J K−1 mol−1, respectively. Glass transitions were found at Tg=(114±1) K in phase III and at Tg=(116±1) K in the supercooled metastable phase II, respectively, and interpreted as attributed to the freezing-in of the rearrangement motion between δ and λ conformations of tmen. The energy difference between the two conformations was less than 0.25 kJ mol−1, and the activation energy for the conformational change was Δea=(33±1) kJ mol−1. The activation energy for the C3 reorientation of methyl groups within the ligand tmen was Δea=(14±1) kJ mol−1.

EPR has been observed in a single crystal of [P(C6H5)4][CuCl3] at room temperature. The spectrum was characteristic of a spin one system, indicating that the copper(II) ions are pairwise coupled in the crystal. The present results agree fairly well with a previous study by Bencini etal. (Inorg. Chem., 1985, 24, 704). From the temperature dependence of the 1H NMR spin–lattice relaxation time, the copper dimer Cu2Cl62- is suggested to have a triplet ground state in accordance with an analysis of the magnetic susceptibility measurements by Estes etal. (Inorg. Chem., 1978, 17, 3657). The exchange interaction between the nearest triplet-state dimers is estimated to be of the order of 10-1 K.

An attempt at modifying the electronic conduction mechanism by guest-host charge transfer and thermally excited molecular motion is reported. Ethylenediamine was intercalated into a semiconducting layered material, titanium disulfide, and a significant increase in charge carriers was evidenced by metallic conductivity, Pauli paramagnetism, and conduction electron spin resonance. Rotational motion of the guest molecule was evidenced by the proton spin-lattice relaxation measurement. However, no anomalous behaviors were found on the electronic properties which are attributable to motion-induced modification of the electronic state.

The NQR frequency and the spin - lattice and spin - spin relaxation times were measured as functions of temperature, in order to study the structural phase transitions in deuterated ammonium hexachloroplumbate(IV) . It was shown that the phase transition at 81 K is of a second-order type with an overdamped soft mode, while the deuteration-induced transition at 38 K is of first order. Three NQR frequencies (17.99, 17.86 and 16.35 MHz at about 15 K) were observed below 38 K suggesting an orthorhombic symmetry in the deuteration-induced low-temperature phase. The averaged value of these frequencies almost coincides with the frequency extrapolated from that (17.348 MHz at 39 K) above 38 K. The splitting (about 1.6 MHz) of the frequency below 38 K is quite large compared with that (0.45 MHz) of , which shows a similar phase transition induced by deuteration at 27.5 K. This indicates a large distortion of the crystal lattice in the present compound.

K2SeCl6 undergoes structural phase transitions of first order at 35 K, 65 K, and 79 K. The temperature dependence of the 35Cl NQR spin-lattice relaxation time suggests that the phase transitions at 65 K and 79 K are displacive ones associated with a resonant soft mode. The presence of a precursor cluster is suggested by the temperature dependence of the signal intensity above 79 K.

Seven new derivatives of 4-octyloxy-N-(4-substituted benzylidene) aniline have been synthesized. 4-Trifluoromethyl and 4-trifluoromethoxy derivatives exhibit stable smectic B and A phases, respectively, while both the 4-methyl and 4-methoxy derivatives have monotropic nematic phases. Fundamental liquid crystalline properties such as entropies of the phase transitions, microscopic textures, smectic layer spacings, orientational order parameters, and molecular dipole moments were determined. It has been revealed that moderately polar nature of these mesogens act to stabilizing monolayer smectic states. The smectic A phase of 4-trifluoromethoxy derivative exhibit very high orientational order. None of the disubstituted compounds, 3,5-bis(trifluoromethyl), 3,5-dimethyl, and 3,5-dimethoxy derivatives were mesogenic. The effect of terminal trifluoromethylation on the liquid crystalline properties is discussed.

An anionic motion in sodium thiocyanate was studied by the spin-lattice relaxation time measurements of 14 N nuclear quadrupole resonance. The relaxation time decreased rapidly obeying an Arrhenius equation above T = 375 K. This result suggests the onset of a head-tail reorientational motion of thiocyanate ion with an activation energy of ≈ 95 kJ mol −1 . The origin of an anomalous temperature dependence of the quadrupole coupling constant is reinvestigated in relation to the anionic motion. It is concluded that a gradual change in electronic state of the anions, not the anionic motion, in the crystal with varying temperature is responsible for the anomaly claimed previously. Intermolecular interaction between N and Na atoms is suggested to be the most important factor in the origin of the change in the electronic state of the anion.

The nature of the smectic Ad to nematic phase transition and the modes of molecular motion were investigated for the homologous mesogens, CBOOA, NBOOA, and their chain-deuteriated compounds. In NBOOA, the SA d[sbnd]N phase transition was found to be first order with a pronounced pretransitional decrease of the orientational order parameter, , both above and below the transition point, while in CBOOA the anomaly in was very small. Despite the different behaviours in terms of the orientational order, the dynamical aspects of molecular motion, probed by the-NMR relaxation, are quite similar. The motional mode characteristic of the N phase is order director fluctuation, but translational self-diffusion becomes the dominant relaxation mechanism in the SA d phase. It is also recognized that the relative importance of these mechanisms changes in a continuous manner as a function of temperature.

Alkali metal-graphite intercalation compounds absorb hydrogen to form alkali metal hydride-graphite intercalation compounds. We investigate the electronic properties and the structures of potassium hydride-graphite intercalation compounds by means of proton nuclear magnetic resonance, Hall effect and UV photoelectron spectroscopy. Among the alkali metal hydride intercalation compounds, potassium hydride intercalation compounds, the structure of which consists of ionic K + H  K + sandwich triple atomic layers between graphitic sheets, were found to have novel two-dimensional metallic hydrogen sheets in the intercalate space.

The nature of smectic A liquid crystals and the phase transitions from smectic A to nematic phases are studied in the homologous series of 4-(4″-octyloxy-benzoyloxy)benzylidene-4′-substituted anilines, in which the substituents are H, F, Cl, Br, I, NO2 and CN. Measurements have been performed for the dipole moment of the molecule, the smectic A lattice period, the temperatures and the entropies of phase transitions, and the temperature dependence of the orientational order parameter, all of which provide information on the intermolecular pair potentials. It is shown that the introduction of a terminal polar substituent brings about counteracting contributions to the stability of the smectic A state. It is suggested that the reentrant nematic phase transition can appear in the strongly polar mesogens if the extent of antiparallel association of the molecules increases on lowering the temperature.

Etude par RMN du compose d'insertion ternaire C 4 KH x (stade 1) prepare a partir d'une intercalation directe de l'hydrure de potassium dans le graphite. Mise en evidence d'un empilement bidimensionnel extremement dense des ions hydrures charges negativement ou le contact direct hydrogene-hydrogene prend place. Observation de la nature metallique de l'hydrogene par le terme de Korringa (T 1 T) −1 =6,4.10 −4 s −1 K −1 (T 1 est le temps de relaxation spin-reseau). C 4 KH x est un exemple d'hydrogene metallique bidimensionnel

Mesomorphic properties are studied on the title compounds where substituents are F, Cl, Br, I, NO2, and CN. Besides the known mesophases, nematic and smectic Ad, in CN and NO2 homologues, stable smectic A and B phases were observed in either of the Cl and Br derivatives. Metastable nematic and smectic A phases were found in F derivative. The effects of terminal polar substituents, stabilization of the smectic A phase by moderately polar substituents, and of the nematic phase by strongly polar substituents, were confirmed.

Differential thermal analysis experiments are carried out on two reentrant liquid crystals, CBOBP and OBBC, whose phase sequences are Crystal–S A1 –RN–S Ad –N–I and Crystal–RN–S Ad –N–I, respectively. The reentrant phase transition (RN/S Ad ) is accompanied by a significantly smaller thermal anomaly than the ordinary ones (S A1 /RN and S Ad /N). S A1 /RN had a larger thermal anomaly than S Ad /N. Comparatively strong temperature-dependence of the heat capacity is suggested in RN. All these findings support the picture of competing incommensurate smectic periodicities and the phenomenological optimum density theory.

Five patients with non-severed traumatic arterial obstruction of the extremity were treated during the last four years. Three were males and two were females. The mean age was 33 years with a range of 5-55 years. The cause of injury was a traffic accident in two patients and in the other three, it was industrial, domestic or iatrogenic. In three patients the obstruction was accompanied by a fracture. The anatomical location of the lesion in the five patients was the external iliac, common femoral, popliteal, axillar or brachial artery respectively. The nature of the obstruction was thrombosis in two patients and extrinsic compression or kinking in three.Only in two patients was the blood supply restored within six hours after injury. In the other three patients, it was restored in about 53, 93 or 172 hours. In all patients, the postoperative course was uneventful.In general, the permissible time lag between the injury and arterial repair is thought to be 6 to 8 hours, but this time lag is not absolute.

Proton spin-lattice relaxation rates were measured in Zeeman and dipolar fields in the liquid crystalline phases (N–S Ad –RN) of OBBC, 4-(4''-octyloxybenzoyloxy)-benzylidene-4'-cyanoaniline. The relaxation mechanisms were analyzed from the frequency- and temperature-dependences of the relaxation rates. The Zeeman relaxation mechanism in the high temperature nemanic (N) phase was characterized by the long-range fluctuation of the nematic director, whereas in the reentrant nematic (RN) phase the relaxation was predominated by translational self-diffusion of molecules. On the other hand, the relaxation in the dipolar frame caused by director fluctuation was observed in all of the three liquid crystalline phases. It is suggested that persistence of nematic director fluctuation in the smectic Ad mesophase is related to the reentrance phenomenon in polar mesogens.

Proton T1D and T1 ρ are measured on ammonium sulfate crystal with 0.8% and 7.3% 17O content, at 30 and 10 MHz. A marked reduction is observed in T1D and T1 ρ compared with normal specimens at temperatures above about 200 K. At 30 MHz, T1D showed a minimum at about 240 K while two minima were observed for T1 ρ in the similar temperature range. Both T1D and T1 ρ at 10 MHz showed different behaviors from those measured at 30 MHz. These experimental results are interpreted in terms of H–O dipole modulation by the SO2−4 reorientation and by the fluctuation of the z component of 17O spin due to strong quadrupole relaxation. From the temperature dependence of the relaxation times, an activation energy of 21 kJ mol−1 and a preexponential factor of 3×10−11 s are obtained for the correlation time of the SO2−4 ion reorientation in the paraelectric phase. The correlation time exhibited a discontinuous change at Tc. Anomalous temperature dependence of the correlation time is observed in the ferroelectric phase. This b...

A case of jejunal diverticulosis with massive melena, of which bleeding point was locally diagnosed by preoperative angiography, is reported. A 52-year-old male with the complaint of massive melena was admitted in pre-shock state. As anemia was not improved by conservative therapy and selective superior mesenteric angiogram revealed a bleeding lesion in the jejunum, emergency operation was performed. Two diverticula were recognized at the mesenteric border of the jejunum about 50cm and 130cm below the ligament of Treitz. Both of them were bilocular, and linear ulcers were found at their septums. A stump of artery was exposed in the ulcer of oral side diverticulum and the source of the bleeding was found macroscopically. Histopathologically a linear ulcer and ruptured artery at the bottom of the ulcer were shown and the additional discussion was made from a point of clinical surgery.

Proton magnetic relaxation times T1, T1ρ, and T1D were measured on a single crystal of α-form oxalic acid dihydrate in two modes: temperature dependence at one or two specific crystal orientations, and angular dependence at several temperatures. Results were compared with the calculation based on an isolated three proton system for the assumed modes of motions. The temperature dependence of T1 and that of T1ρ and T1D in the low temperature range are reasonably accounted for by the 180°-flip of the water molecule. The activation energy for the motion of 43.6 kJ mol−1 is obtained. T1ρ and T1D above about 35 °C decreased as the temperature was raised. The comparison of the observed results in this temperature range with the calculated ones suggests that there is exchange motion among the three spins. An activation energy for this motion of 80.8 kj mol−1 is obtained. This three spin exchange motion may be considered as a combination of a jump of carboxyl proton to a higher potential trough corresponding to th...

During the past five years, arterial reconstruction was performed in five cases of chronic maintenance hemodialysis for complications of arteriovenous fistula. The subjects were three males and two females. The cases of arteriovenous fistula with complications involved three cases of arteriovenous fistula between the cutaneous veins proximal to the brachial artery, one case of gore-tex graft arteriovenous fistula between the brachial artery and vein and one case of bovine graft arteriovenous fistula between the femoral artery and vein. The complicatons for which arterial reconstruction was necessary involved four cases of intrafistular infection and one case of acute arterial embolism. In the four cases of infection, autoplasty of the venous bypass was performed, bypassing the involvement and passing under the medial skin at the elbow joint area. This course was considered to be appropriate because the graft was not bent by movement of the joint. In the one case of arterial embolism, embolectomy was performed with a Fogarty catheter. The most troublesome complication was that of infection, and much care must be taken to prevent infection in arteriovenous fistulation or intrafistular puncture.

A 28-year-old man was evaluated for complaining of dyspnea. Chest X-ray film revealed a right sided pneumothorax with complete collapse. A thoracic tube was inserted and slowly drainaged, because there was a possible occurrence of Reexpansion pulmonary edema (REPE) with a lapse of 42 days after the onset. About 3 hours after drainage, he complained of cough, dyspnea and chest pain. Chest X-ray film revealed glass-like shadows. Immediately, thoracic tube was connected to the continuous suction at the pressure of -12 cmH2O. At the same time, 0.2 supply and injection of steroid were started. On the next day, these symptoms were improved. His chest X-ray film returned to normal within a week. There were 12 cases of spontaneus pneumothorax during the past 3 years in our hospital, of which 3 were complicated by REPE. In all the 3 cases, complete collapse of the lung due to pneumothorax had existed for 3 days or more. In the treatment of these cases, it is necessary to consider REPE.

The quadrupole spectra of deuteron magnetic resonance were observed on single crystals of (ND4)2C2O4D2O. The quadrupole coupling tensors for stationary deuterons were determined at −110°C. eqQ⁄h and η are 163.7–172.8 kHz and 0.005–0.015 for the ammonium deuterons and 213.3 kHz and 0.090 for the water deuteron. The eqQ values and principal axis directions of EFG tensors are consistent with the structure deduced from the diffraction studies with the exception that the z principal axes of D in the ammonium ion deviate appreciably from the NH directions derived from neutron diffraction. From the change in the line-width with the temperature, the rate of the C3 reorientation of ammonium ions and that of the 180° flip of water molecules were estimated at various temperatures. The ammonium-ion reorientation is found to be quite isotropic. The temperature dependence of the proton T1 and T1ρ and the deuteron T1 were measured on (NH4)2C2O4H2O and (ND4)2C2O4D2O powers. The T1 values were then compared with the calcu...

A deuteron magnetic resonance study was made on four compounds with an O—D···O hydrogen bond of different strengths. The deuteron quadrupole coupling constant eqQ, asymmetry parameter η, and the directions of the field gradient tensor were determined. The eqQ and η obtained are: KDCO3154.4±0.6 kc/sec,0.194±0.018,(COOD)22D2O D1(water)230.3±2.0 kc/sec,0.062±0.006,D2(water)219.1±2.0 kc/sec,0.16±0.03,} (at−70∘C) D1 and D2121±3 kc/sec,0.93±0.02,(at 67∘C) D3(carboxyl)139.2±0.8 kc/sec,0.098±0.005,ND4D2PO4 (acid D)119.6±0.8 kc/sec,0.053±0.008,K, D−maleate 56.0±0.8 kc/sec,0.53±0.07.The results are discussed in relation to the crystal structure in each case. It was found that the oxalic acid dihydrate crystal used was a new modification, different from the ordinary one. Reorientational motion of a water molecule similar to that in other hydrated crystals was observed in oxalic acid dihydrate from the measurement at different temperatures. A barrier to this motion of 10.0 kcal/mole was determined from the te...

A deuteron magnetic resonance study has been made on a single crystal of urea-d4. At room temperature deuteron quadrupole coupling corresponding to a stationary molecule is obtained. The eqQ and η values determined are: eqQ⁄h=210.8±1.0 kc./sec. and η=0.139±0.010 for D1, and eqQ⁄h=210.7±1.0 kc./sec. and η=0.146±0.010 for D2 at room temperature, and eqQ⁄h=206.3±1.2 kc./sec., η=0.138±0.010 for D2 at 117°C. In both cases the maximum field gradient component and the N–H direction are in good agreement. The onset of reorientational motion about the C=O bond of a whole molecule has been concluded from the line-width change at high temperatures. Above 110°C the effect on the line-width of the reorientation about C–N bond has also been observed. The barrier heights for these motions are estimated to be 11±2 kcal./mol. for the reorientation about the C=O bond and 15±3 kcal./mol. for that about the C–N bond. The temperature dependence of the quadrupole splitting and that of the dipole coupling between 14N and D have...

The pure quadrupole resonance spectra were observed on Cl 35 and Cl 37 in BCl 3 and Br 79 and B 81 in BBr 3 at several temperatures. The spectrum of each nucleus consists of characteristic doublet (ν I and ν II ) with the intensity ratio of ca. 3 to 5. The Zeeman study with a single crystal of BBr 3 was also carried out at liquid nitrogen temperature (77°K), to determine the asymmetry parameter η. The results are as follows

Deuteron magnetic resonance is measured on a LiOD single crystal, and deuteron quadrupole coupling is determined at various temperatures from 77° to 683°K. The quadrupole coupling constant at 77°K is 327.0 kc/sec. From a point‐charge calculation it is concluded that the deuteron quadrupole coupling is almost entirely intraionic in origin. The value appears to represent a quadrupole coupling for a non‐hydrogen‐bonded O—D bond. The agreement of the field gradient at D with the force constant of the OH stretching vibration of LiOH is excellent. The temperature dependence of the field gradient can be explained by the OD libration of 330 cm−1, which is somewhat higher than the librational frequencies determined by spectroscopy. No appreciable anharmonicity of the librational oscillation is indicated in the temperature range of observations. The rotational motion of OH− in LiOH is unlikely. The 7Li quadrupole coupling is also determined at room temperature and at 683°K. The quadrupole coupling constant at room temperature is 94.5 kc/sec.

Deuteron magnetic resonance study was made on single crystals of NiSiF6·6D2O and NiSnCl6·6D2O. Deuteron quadrupole coupling tensors were determined at various temperatures. In NiSiF6·6D2O, the quadrupole coupling at −116°C is that of stationary D2O, at 23°C and at 70°C that of D2O under rapid 180°-flip motion and at 150°C that of rapid Ni(D2O)62+ reorientation. The eqQ⁄h values at −116°C, 238.3±1.3 kc and 235.7±1.9 kc do not appear to show marked effect of strong coordination. In NiSnCl6·6D2O, the quadrupole coupling corresponding to D2O under 180°-flip motion is observed at −53°C, at 25°C, and at 55°C. Spectra corresponding to a stationary D2O are not observed even at 77 °K. From the orientation of quadrupole tensors probable crystal structures of these compounds are proposed. Line width transitions were observed from which the reorientation rate was derived. The estimated activation energies of the 180°-flip motion of D2O are 7.6 and 4.3 kcal/mol in the fluosilicate and chlorostannate, respectively, and...

Deuteron magnetic resonance (DMR) of single crystals of Cu(DCOO) 2 ·4D 2 O has been studied from 153°K to 291°K to reveal the changes in the structure and the motions of the crystalline water molecules due to the paraelectric-antiferroelectric phase transition ( T c =246.1±0.2°K). Above T c , all the DMR lines of water molecules are broadened out by fast motions of deuterons among seven sites. Below T c , 20 pairs of DMR lines are observed corresponding to four water molecules in stable position and two formate ions and their a c -plane enantiomorphs. Following conclusions are derived from measurements of temperature and angular dependences of the quadrupole splittings for these DMR lines. The phase transition is an order-disordering type of water molecules. In the antiferroelectric phase, the unit cell doubling occurs along the c -axis direction and the space group is P 2 1 / n . The structure involves a three dimensional ordering of water molecules. The structure of hydrogen-bond network is determined. ...

Quadrupole splitting of deuteron magnetic resonance was measured for a single crystal of Ba(ClO3)2·D2O. Quadrupole coupling, asymmetry parameter, and principal axis directions of the field gradient tensor were determined at 20° and at —130°C. eqQ/h=121.5±0.4 kc/sec, η=0.976±0.007 at 20°C, and eqQ/h=243.5±1.5 kc/sec, η=0.074±0.002 at —130°C. The field gradient at room temperature shows a rapid reorientation of the water molecule in a crystal. At room temperature, the spectral line exhibits fine structure due to coupling of two spins, which was utilized to determine the sign of eqQ in the present case.The line broadening effect in the intermediate temperature region (—45°∼—121°C) was measured and was used to obtain the reorientation rate at various temperatures. The barrier to reorientation of 6.6 kcal/mole was obtained from the comparison of the experimentally determined reorientation rate with that calculated from a tunneling process through a hindering barrier, or that of 6.5 kcal/mole from classical pro...

A deuteron magnetic resonance study is made of single crystals of CuSO4·5D2O between 130° and 360°K. The electric quadrupole coupling constant, the asymmetry parameter, and the directions of the principal axes of the field‐gradient tensor are determined for each deuteron at 133.2° and 294.8°K. At low temperatures ten pairs of lines are observed, corresponding to five nonequivalent stationary water molecules. At temperatures above room temperature, five pairs of lines are observed; these are shown to result from fast molecular reorientation about the bisecting axis of each water molecule. An activation energy for the 180° reorientational motion is derived for each water molecule and is discussed in relation to the lonepair coordination of the oxygen atom of the water molecule and the hydrogen‐bond strength. The field‐gradient tensor for each stationary water molecule is discussed in relation to the structure of the hydrogen‐bond system. For relatively weak asymmetric hydrogen bonds of O–H···O, an empirical...

A study on the Zeeman effect of Cl 35 nuclear quadrupole resonance spectrum was carried out on a single crystal of cyanuryl chloride. Three distinct q -tensors were found in this crystal, two of them being equivalent. The directions of the principal axes were determined within the accuracy of 1° . It was concluded that in the crystal all molecules are disposed parallel (or antiparallel) to one another and three C–Cl bonds of a molecule are on a plane, making an angle 120° with one another, one of them being not equivalent to the other two. A large asymmetry parameter, 0.26, was obtained. From the coupling constant and the asymmetry parameter, the double bond character and the ionic character of C–Cl bonds were estimated to be 10% and 17%, respectively. The large double bond character was considered to be associated with the large electronegativity of nitrogen atoms in the ring.

The temperature dependence of the dipole moment was investigated on monochloromethyl ether (I), sym-dichloromethyl ether (II) and monobromomethyl ether (III) in the gaseous state, and (III) and sym-dibromomethyl ether (IV) in heptane solution. The moment of (I), (II) and (IV) increases with temperature, while that of (III) does not. From the observed data the energy difference between the gauche and the trans position is 0. 7 kcal./mol. in (I), and zero in (III) Similarly ΔE’s between t,g- and g,g-form of (II) and (IV) are estimated to be 1.3 kcal. and obtained to be 0.9 kcal./mol. respectively from the observed results.

Deuteron quadrupole coupling tensors in Co(ND3)6Cl3 were determined at various temperatures. The observed quadrupole coupling shows that Co(ND3)63+ ions execute a rapid isotropic reorientation at high temperatures (above 320°K for one of the sites (the 4f sites) and above 190°K for another (the 2e sites), while at low temperatures (below 190°K for the 4f sites, and 170°K for the 2e sites), only a C3 axis reorientation of the ligand ND3 groups is present. The deuteron resonance spectra clearly show that Co(ND3)63+ ions in the 4f sites begin to reorient about one of the three C4 axes at intermediate temperatures (about 240°K). On the basis of the orientation of quadrupole tensors, probable orientations of Co(ND3)63+ ions in the 4f sites in the crystal are proposed. Additional measurements of the proton resonance on a single crystal of Co(NH3)6Cl3support the results obtained from the deuteron resonance. To obtain the reorientation rates and the activation energies of these reorientational motions, the deuter...

The dipole moments of propargyl chloride, bromide and monochlorobutyne in the gaseous state are measured to be 1.65D,1.52D and 2.17D respectively. The moment of propargyl chloride and bromide are considerably smaller than the saturated one even though the correction of C≡C—C skeletal moment is taken into account. This is consistent with the —CH2Cl group moment of dichlorobutyne obtained in the preceding work. These results are inconsistent with the resonance scheme presented by Pauling et al. for propargyl halide. The anomaly is considered as a characteristic feature of the molecules having triple bonds of this kind. By taking all of the moments of dichloro- and monochlorobutynes and propargyl chloride into account, the bond moments, the induction moments and the direction of the resultants, are predicted as shown in Fig. 1.

The dipole moment measurement was made at various temperatures on ethyl, i-propyl and t-butyl nitrites. Observed moments are 2.41D for ethyl, 2.57D for i-propyl, 2.70D for t-butyl nitrite at room temperature. The moment of the latter two compounds decrease slightly with temperature while ethyl compound remains constant. These esters are considered to consist of two isomers: the trans and the cis separated by a barrier of several kcal. due to a resonance effect. The energy difference ΔE between the two isomers is found to be zero in ethyl

An apparatus for the measurement of dielectric constant in the gaseous state is constructed. The electrical circuit is a heterodyne double-beat type, the oscillators with a remarkably high frequency stability are constrcuted. By testing several types of gas cell, it was found that one of them (cell D) can be used satisfactorily for the present purpose. For the gas filling system, a modification of Groves’ method is employed. Using this apparatus dielectric constant measurement with an error of less than 0.5 per cent can be obtained. The dipole moment of 1,1-dichloroacetone was measured in this apparatus. The moment was found to increase with temperature. This increase is attributed to the increase of the more polar isomer (b), which coexists with the form (a). The energy difference of the two isomers was found to be about 800 cal./mole. This value is smaller than that of monochloroacetone, and the lowering of ΔE was considered to be due mainly to the reduced moment of the C-Cl bonds by mutual induction. I...

Deuteron magnetic resonance study is made of single crystals of LiD 3 (SeO 3 ) 2 between -143°C and 110°C. The electric quadrupole coupling constant, e Q q / h , the asymmetry parameter, η, and the directions of the principal axes of the field-gradient tensor are determined for each deuteron at room temperature. Three non-equivalent tensors are obtained corresponding to the three non-equivalent fairly strong hydrogen bonds determined by X-ray diffraction. The e Q q / h and η are 107.8 kc/sec and 0.172 for D a , 127.9 kc/sec and 0.154 for D b , and 181.1 kc/sec and 0.101 for D c , The hydrogen-bond network in LiD 3 (SeO 3 ) 2 is determined. The atomic coordinates of deuterons are estimated from the results of the present DMR study. The field-gradient tensor of 7 Li is also determined at room temperature. The values of e Q q / h and η are 33.9 kc/sec and 0.593.

Deuteron and 23 Na magnetic resonances are measured of single crystals of NaD 3 (SeO 3 ) 2 between 134°K and 298°K to reveal the nature of the ferroelectric transition ( T c ∼267°K). Deuteron resonance lines D a and D b (relative intensity 1:2) above T c split into two and into four, respectively. The 23 Na resonance line above T c also splits into two below T c . Following conclusions are derived from measurements of temperature and angular dependences of the quadrupole splittings for these deuteron and 23 Na resonance lines. All the hydrogen atoms are linked with moderately strong hydrogen bonds, and are jumping back and forth in the double well potential above T c . The phase transition is accompanied not only by order-disordering of hydrogen atoms in hydrogen bonds, but also by slight rotations of SeO 3 - ions and by a slight distortion of lattice in the neighborhood of Na + ions. The crystalline symmetry below T c is monoclinic, and the cell-doubling occurs along the b axis. Hydrogen-bond network bel...

四塩化炭素を開始剤に用い,三塩化チタンートリエタノールアミンにより-10℃ 前後の温度で重合したポリ塩化ビニル(PVC)の広幅およびパルスNMRを行ない市販品と比較した。試料は常法で精製し市販品は減圧乾燥して用いた。低い温度で重合したPVCの広幅スペクトルはある温度範囲で二つに分れる。吸収の広い部分がポリエチレンのように結晶に基くとすれぽ,動的結晶度は30～40%になり,110℃ 以下でその幅は変らないが,これを超えると運動は急に開放される。ポリエチレングリコールを加えて乳化重合したものには,50℃ 以上で鋭い吸収が現われ,これを精製しても消えない。スピン格子緩和の機構は簡単でなく,緩和時間(T1)は二つ以上含まれる。T1の温度依存性から分子運動を考察した。-196℃ で広幅スペクトルの吸収幅はどのPVCも期待される値よりやや大きく,塩素核による核四重極効果が考えられる。

The dipole moment of acenaphthene (I) was measured in the gaseous phase as 0.93D. Measurement in benzene solution at 25°C gave the following moment values: acenaphthene (I) 0.85D; 5-chloroacenaphthene (II) 2.50D ; and 5,6-dichloroacenaphthene (III) 3.85D. By the comparison with the moments of naphthalene derivatives it was shown that the moments of (II) and (III) are approximately equal to the sums of the moment of (I) and the moments arising from one and two C–Cl bonds, respectively.