Incoherent Inelastic Neutron Scattering data and new infrared spectra were acquired in order to examine both the external and internal vibrations in crystalline L-alanine. For the first time we observe a splitting of the NH3 + torsional band below a temperature of approximately 220 K as well as an overtone of this band. The intensity of both of these bands is strongly dependent on temperature. Birefringence and depolarization measurements performed with single crystals reveal a subtle breaking of symmetry around 220 K perhaps involving the hydrogen bond networks. We show that this instability cannot, however, be the origin of the observed splitting. Instead, the anomalous temperature dependence of the observed intensity and frequency of the torsional mode and its overtone may be explained on the basis of a nonlinear coupling of the NH3 + oscillator with lattice phonons. This leads to localization of vibrational energy, a so-called “breather” or “vibrational polaron”.

The solubility of Nd 2 O 3 in NdF 3 -LiF-MgF 2 melts is about 0.08-0.38 mol% when the NdF 3 concentration varies from 15 to 30 mol% at 900 ЊC. The solubility increases from 0.13 mol% at 750 ЊC to 0.22 mol% at 900 ЊC in the NdF 3 -LiF eutectic. When MgF 2 is added to NdF 3 -LiF binary melts saturated with Nd 2 O 3 , the Nd 2 O 3 solubility seems to decrease slightly at 30 mol% NdF 3 , while a slight increase was observed with 15 mol% NdF 3 in the binary. When dissolving Nd 2 O 3 in the NdF 3 -LiF eutectic Raman spectroscopy showed that the complex ions NdOF (x Ϫ 1)Ϫ x and Nd 2 OF (x Ϫ 1)Ϫ x ϩ 3 may form in the melt. The most reasonable candidates seem to be: NdOF 4 3Ϫ and NdOF 5 4Ϫ among the mononuclear compounds and Nd 2 OF 10 6Ϫ , Nd 2 OF 8 4Ϫ among the binuclear complexes. I ANISO (ω) = I HV (ω) (2) DALTON

Abstract. This paper discusses the highlights of the EU-funded "Assimilation of Envisat data" (ASSET) project, which has involved assimilation of Envisat atmospheric constituent and temperature data into systems based on Numerical Weather Prediction (NWP) models and chemical transport models (CTMs). Envisat was launched in 2002 and is one of the largest Earth Observation (EO) satellites ever built. It carries several sophisticated EO instruments providing insights into chemistry and dynamics of the atmosphere. The overarching theme of the ASSET project has been to bring together experts from all aspects of the data assimilation problem. This has allowed ASSET to address several themes comprehensively: enhancement of NWP analyses by assimilation of research satellite data; studies of the distribution of stratospheric chemical species by assimilation of research satellite data into CTM systems; objective assessment of the quality of ozone analyses; studies of the spatial and temporal evolution of tropospheric pollutants; enhanced retrievals of Envisat data; and data archival and dissemination. Among the results from the ASSET project, many of which are firsts in their field, we can mention: a positive impact on NWP analyses from assimilation of height-resolved stratospheric humidity and temperature data, and assimilation of limb radiances; the extraction of temperature information from the assimilation of chemical species into CTMs; a first intercomparison between ozone assimilation systems; the extraction of information on tropospheric pollution from assimilation of Envisat data; and the large potential of the Envisat MIPAS dataset. This paper discusses these, often novel, developments and results. Finally, achievements of, and recommendations from, the ASSET project are presented.