A novel cryostat was developed for in situ neutron scattering studies on vapor-deposited amorphous samples. By the use of this cryostat, vapor-deposited amorphous ice was prepared at ca. 8 K. The neutron scattering spectra of the as-deposited sample and those annealed at ca. 120 K, 160 K, and 250 K were measured at 50 K in energy range below 100 meV. The four samples studied corresponded to vapor-deposited amorphous solid water (ASW), hyperquenched glassy water (HGW) (approximately), ice Ic, and ice Ih, respectively (according to historical nomenclature). The librational frequency of the water molecule is smaller in the order of ASW<HGW<Ih(≈Ic). This indicates that the strength of the intermolecular hydrogen bonds is Ih(≈Ic)>HGW>ASW. The absolute value of the vibrational density of states G(E) was obtained from the analysis combining the heat capacity and neutron scattering data. G(E) of ASW and HGW integrated below 6 meV were larger than that of ice Ih(≈Ic) by 0.060 and 0.039 degrees of freedom per water molecule, respectively. Similar experiments were performed on the vapor-deposited amorphous ice doped with 5% and 10% of methanol (CD3OH). The magnitude of G(E) below 6 meV increased with increasing fraction of methanol. All of the results in this study indicate that the low energy excitation [G(E) below 6 meV] of amorphous ice is enhanced by the defects and distortion of the hydrogen bonds.

The heat capacity of cyclooctanol was measured with an adiabatic calorimeter in the temperature range 5-340 K. Liquid cyclooctanol crystallized into crystal I, a plastic (orientationally disordered) phase. Crystal I was supercooled readily and underwent a glass transition at 160 K. Crystal II, obtained by annealing crystal I at about 200 K, also underwent a glass transition at 160 K, indicating that crystal II is also an orientationally disordered phase. On heating, crystal II transformed to crystal I at 261.7 K with a transition entropy of 8.06 J K −1 mol −1 and crystal I fused at 295.3 K with a fusion entropy of 7.00 J K −1 mol −1 . Neutron scattering of cyclooctanol was measured in the temperature range 20-335 K, energy range 0.1-20 meV and momentum transfer range 0.23-2.7 Å −1 . A clear boson peak was found around 2.5 meV in both orientational glasses of crystal I and II. Quasielastic scattering appeared at temperatures as low as the glass transition temperature. This may be due to a fast β process which has been observed in most glass-forming liquids. The present results indicate that glass-forming plastic crystals are similar to glass-forming liquids in their dynamical properties in terahertz region.

The heat capacities of the glassy and liquid states of three lithium chloride aqueous solutions (LiCl⋅4H2O,LiCl⋅6H2O,LiCl⋅7.5H2O) were measured with an adiabatic calorimeter in the temperature range 5–340 K; the crystalline state was also measured for LiCl⋅4H2O. For all of the glassy samples, a large non-Debye excess heat capacity appeared below 30 K. The neutron scattering spectra of glassy LiCl⋅4H2O and LiCl⋅6H2O were measured with two spectrometers operating with different energy windows (E<20 meV and E<100 meV). A boson peak, corresponding to the excess heat capacity, appeared at around 4 meV in the S(Q,E) spectra of both glassy samples. From the analysis combining the heat capacity and neutron scattering data, the excess density of states due to the boson peak (compared with hexagonal ice) was found to be 0.10 degree of freedom per water molecule for both glassy samples. A librational peak of water molecules appeared at around 60 meV in glassy samples. This energy is about 10 meV lower than that of hexagonal and amorphous ices, indicating that the hydrogen bonds connecting water molecules are broken due to the strong coordination of water molecules to lithium ions.

The reaction of PdCl2(PhCN)2 with ethyl α-N-acetyl-β-(4,6-dimethylbenzofuran-2-yl)acrylate, having a Z-propenyl group at 2-position of benzofuran ring, gave an azepine derivative, whereas its E-isomer afforded a Pd-σ-complex having azepine skeleton. Configurational assignment of the σ-complex, accomplished by methoxycarbonylation, clearly demonstrates that this intramolecular aminopalladation proceeds via cis-aminopalladation.

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