Electron-diffraction study of hydrogen isotope effects in cyclohexane

The electron-diffraction data for cyclohexane and perdeuterated cyclohexane were analyzed and the results were compared. It was found that r_g(C-C) = 1.535 Å (±0.002) for both compounds; r_g (C-H) = 1.116 Å (±0.004) and r_g(C-D) = 1.109 Å (±0.003). Observed hydrogen isotope effects in mean amplitudes agree very well with calculated ones. The C-C bond distance of cyclohexane is in good agreement with some of the previous studies, which is of importance in view of a recent scaling controversy involving this parameter.     

The temperature dependence and anisotropy of the thermal conductivity in polyacetylene

Observations of anisotropic transport in (CH)_x reported to date have been made on stretch-oriented films in the plane of the film. We report the first observations of anisotropy in the thermal conductivity measured parallel and perpendicular to the plane of unstretched films. The room-temperature value measured along the film is $\text{50}\text{mW}\text{cm}\text{?}\text{K}$, and is almost a factor of 20 higher than that observed perpendicular to the film $\text{(}\text{3}\text{mW}\text{cm}\text{?}\text{K}\text{)}$. Finally, the temperature dependences for the parallel and perpendicular thermal conductivities are reported.     

Temperature dependence of the thermal conductivity for tellurium dioxide

The thermal conductivity of tellurium dioxide is reported as a function of temperature. At 77K, the thermal conductivity is 0.09 W/cm-K and it decreases approximately as the inverse of the temperature to a value of 0.02 W/cm-K at 300K. The anisotropy between the a- and c-axes is less than 20% over the entire experimental temperature range, with the a-axis more conductive than the c-axis. By making some simplifying assumptions, the phonon mean free paths and relaxation times are deduced.     

The decay of93g Ru,93m Ru,91g Mo,91m Mo,91g Tc and91m Tc

Decay studies on a number of short-lived odd nuclei in theN=50 region are described. The 59.6-s ⁹³Ru ground state decay was studied in detail for the first time; in these experiments the 10.8-s activity^93m Ru was discovered. The⁹¹Tc activities were also observed for the first time. The ground state and an isomeric state of this nucleus decay with nearby equal half-lives (3.14 and 3.3-min). The activities^91g Mo (16.6-min) and^95m Mo (65.1-s) have been reinvestigated. A number ofγ-rays, previously erroneously assigned to the⁹¹Mo activities, could be eliminated. A strong similarity is noted for the decay schemes of theN=49 isotones^91m Mo and^93m Ru. The energy of the 1/2^? isomeric state in⁹³Ru and theB(M4)-value of the isomeric transition fit well into the systematics of the previously knownN=49 isotones.     

Complex formation and kinematic coupling: complexed ethylene

The hypothetical system of an ethylene-thallium(III)-water complex, C₂H₄-Tl³⁺-H₂O, was used to demonstrate in principle the possibility of kinematic couplings between internal ligand and complex framework vibrations in an organometallic complex.