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The need for a safe, reliable and cheap method for hydrogen transportation has prompted an intense effort in the synthesis of novel hydrides. To direct the search for better materials, it is essential to understand the bonding present in these systems. A newly synthesized material is LaMg2PdH7 which is best formulated as {La3+}{Mg2+}2{[PdH4]4−}{H−}3. Thus hydrogen is formally present both as a free hydride ion and also as a covalently bound ligand. The combination of inelastic neutron scattering (INS), infrared and Raman spectroscopies and periodic density functional theory (DFT) has been used to characterise the material. We find that the material is less ionic than Ba2[PdH4], which also contains [PdH4]4−. The charges carried by both the coordinating and free hydrides are similar which hints at a degree of covalency in the interactions between the interstitial hydrides and the lanthanum and magnesium ions.

A multivariate approach to the analysis of cured resin blends comprising cyanate ester and bismaleimides is reported. An analysis of samples subjected to accelerated ageing tests by immersion in water at temperatures up to 70 °C shows that simple near infrared spectroscopic measurements on virgin materials can predict dynamic mechanical thermal analysis results, and provide correlations with thermogravimetric analysis. This suggests a rapid screening method for a range of materials, perhaps in conjunction with a combinatorial approach to advanced composites manufacture.

The use of inelastic neutron scattering (INS) spectroscopy has allowed the determination of the infrared and Raman inactive out-of-plane bending mode ν 5 in the [PdCl 4 ] 2− ion at 136 cm −1 . To our knowledge, this is the first time this mode has been observed in any homoleptic square planar complex. An initial highly anomalous INS spectrum was shown by the use of Raman microscopy to be due to an impurity phase that is most probably a hydrate.

The inelastic neutron scattering and high-resolution FT-Raman spectra of methyltrioxorhenium are reported. Literature assignments of the modes below 1600 cm −1 are largely confirmed with the exceptions of the methyl torsion and the ReO 3 bending modes. The methyl torsion is observed for the first time at 200 cm −1 , while the band at 230 cm −1 assigned previously to the torsion is shown to be a component of the factor group splitting of the solid. In the FT-Raman spectrum, the bands that derive from the E modes in the isolated molecule are split by the C s site symmetry of the crystal. This allows an unambiguous assignment of these modes to be made. On this basis, the assignment of the ReO 3 bending modes is reversed with the asymmetric mode at 325 cm −1 and the symmetric mode at 276 cm −1 .

High resolution, high signal-to-noise ratio Fourier transform Raman (1 cm−1) and infrared spectra of perdeutero-polyethylene have been measured Observation of the residual isolated CH stretch modes has been used to derive a CH bond distance in reasonable agreement with experimental data. Some combination and overtone modes are observed and assigned for the first time. The high resolution has allowed upper limits for the correlation splitting of the Raman bands to be set. Curve resolution of the broadest band, 1251 cm−1 has allowed observation of the correlation split components and a third band that is assigned to the amorphous region of the polymer.

A one-dimensional coupled diffusion and chemical reaction steady-state problem in spherical geometry has been considered. This type of problem is often encountered in atmospheric chemistry when dealing with uptaking of gaseous pollutants in cloud or fog drops. A closed form fundamental solution of the governing equation has been obtained. Making use of this solution and following the standard BEM approach, the boundary value problem under consideration has been transformed into a nonlinear integral equation. The discretization of this equation resulted in a set of nonlinear algebraic equations solved by the Newton-Raphson solver. For specific, linear cases the results obtained have been compared with analytical solutions available in the literature. Good accuracy has been observed. Numerical examples dealing with two coupled nonlinear equations describing diffusion with chemical reaction of two species have been included.