A computed list of HD16O infrared transition frequencies and intensities is presented. The list, VTT, was produced using a discrete variable representation two‐step approach for solving the rotation–vibration nuclear motions. The VTT line list contains almost 700 million transitions and can be used to simulate spectra of mono‐deuterated water over the entire temperature range that are of importance for astrophysics. The line list can be used for deuterium‐rich environments, such as the atmosphere of Venus, and to construct a possible ‘deuterium test’ to distinguish brown dwarfs from planetary mass objects.

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Time-and temperature-resolved infrared absorption spectroscopy is used to monitor the ligand substitution reaction of W(CO) 5 (cyclohexane) with a series of ligands L of the form cyclo-C 4 H n O (n ) 4, 6, 8). Secondorder rate constants for the formation of W(CO) 5 (L) are obtained over the temperature range 20-60 °C, and from these temperature-dependent rate constants, activation parameters for the ligand substitution reaction are obtained. We find that for L ) furan, ∆H ‡ ) 7.1 ( 0.7 kcal mol -1 and ∆S ‡ ) -7.1 ( 5.1 eu; for L ) 2,3-dihydrofuran, ∆H ‡ ) 5.9 ( 0.5 kcal mol -1 and ∆S ‡ ) -8.9 ( 7.3 eu; and for L ) 2,5-dihydrofuran, ∆H ‡ ) 3.8 ( 0.2 kcal mol -1 and ∆S ‡ ) -14.0 ( 3.5 e.u. We find that as L becomes less strongly electrondonating, as determined by the trans C-O stretching force constant of W(CO) 5 L, ∆H ‡ rises and ∆S ‡ becomes less negative. The correlation of the activation enthalpy with the properties of the products and the low activation enthalpies relative to the (CO) 5 W-cyclohexane bond dissociation energy are consistent with an associative interchange (I a ) mechanism for the ligand exchange.

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The diffusion coefficients of iron (II) ions depositing on solid tungsten electrodes in a molten chloride systems at about 700°C have been determined by electrochemical techniques. The deposition process occurs under diffusion control for all the iron concentrations and temperatures studied. Conventional cyclic voltammetry and convolution cyclic voltammetry methods were used. Diffusion coefficients of iron (II) were calculated according to Randles‐Sevcik and Berzins‐Delahay equations for the conventional cyclic voltammetry and also by the limiting convoluted current for the convolution cyclic voltammetry. Convolution cyclic voltammetry is believed to be superior to conventional cyclic voltammetry for the quantitative evaluation of diffusion coefficients. The values of the diffusion coefficients lay in the range 1‐40‐10−5 cm2/s for the temperature range of 700‐750°C. The Arrhenius temperature dependence of the diffusion coefficients is characterized by the value of Ea = 31.2 kJ/mol.