RESUMO
We use 1H, 2H, and 7Li NMR to investigate the molecular dynamics of glass-forming LiCl-7H2O and LiCl-7D2O solutions confined to MCM-41 or SBA-15 silica pores with diameters in the range of d = 2.8 nm-5.4 nm. Specifically, it is exploited that NMR experiments in homogeneous and gradient magnetic fields provide access to local and diffusive motions, respectively, and that the isotope selectivity of the method allows us to characterize the dynamics of the water molecules and the lithium ions separately. We find that the silica confinements cause a slowdown of the dynamics on all length scales, which is stronger at lower temperatures and in narrower pores and is more prominent for the lithium ions than the water molecules. However, we do not observe a temperature-dependent decoupling of short-range and long-range dynamics inside the pores. 7Li NMR correlation functions show bimodal decays when the pores are sufficiently wide (d > 3 nm) so that bulk-like ion dynamics in the pore centers can be distinguished from significantly retarded ion dynamics at the pore walls, possibly in a Stern layer. However, we do not find evidence for truly immobile fractions of water molecules or lithium ions and, hence, for the existence of a static Stern layer in any of the studied silica pores.
RESUMO
The atypical antipsychotic zotepine was studied in an open, multicentre uncontrolled, post-marketing surveillance study in 108 schizophrenic patients hospitalized in 12 trial centres in Austria. Within the dosage range of 50-450 mg (mean at the end of the study, 207 +/- 125 mg/day), a significant reduction of positive as well as negative symptoms was noted. There was no increase in extrapyramidal side-effects during the study and a significant decrease in akathisia scores. The medication was well tolerated during the 42-day observation period. Zotepine improved both positive and negative symptoms and was not accompanied by extrapyramidal side-effects, justifying its classification as an atypical antipsychotic.