Michael Galle

Rational Design of Cation Hosts – Prediction of Cation Selectivity by Quantum Chemical Calculations

Summary Structures of [M ⊂ 2.2.2]n+ obtained with MNDO, AM1, PM3, PM3/SPASS, and PM5, are evaluated against X-ray and DFT (B3LYP/LANL2DZp) geometries. DFT and X-ray structures agree well, followed by PM3/SPASS. The ion selectivity calculated with DFT and PM3/SPASS for a simple model reaction, agrees satisfactorily with the available complex-formation constants (log KS). The applied theoretical treatment has a good predictive potential.

WebAssist: a user profile specific information retrieval assistant

Abstract Despite the ever increasing information available on the Internet today, finding accurate information for a specific topic becomes more and more difficult. This paper describes the concept of a proxy based information classification and filtering utility, named WebAssist. On the behalf of users a private view of the WWW is generated based on a previously determined profile. This profile is created by monitoring the user (and group) activities when browsing WWW pages. Additional features are integrated to allow for easy interoperability in workgroups with similar project interests, maintain personal and common hotlists with automatic modification checks and a sophisticated search engine front-end. The proxy architecture allows easy configurability using standard Web browsers and eliminates the necessity to install additional platform specific software.

Protonen on Tour – DFT-Studie zur H+-Wanderung in [1.1.1]- und [2.2.2]-Cryptanden / Protons on Tour – DFT-study of H+-Migration in [1.1.1]- and [2.2.2]-Cryptands

DFT-calculations (RB3LYP/LANL2DZp) show that the migration of a proton inside [1.1.1]- and [2.2.2]-cryptand from one nitrogen atom to the other follows different paths. While the proton in [H⊂1.1.1]-cryptand moves via an ether oxygen atom (activation energy: 19.2 kcal/mol), the proton in [H⊂2.2.2]-cryptand moves directly from one nitrogenatom to the other (activation energy: 16.1 kcal/mol). Our calculations rule out the application of doubly protonated [2.2.2]-cryptands as anion hosts.

Die Zaubervorlesung: „Chemie am laufenden Band”

Jedes Jahr zum Anfang des Wintersemesters findet an der Friedrich Alexander Universitat Erlangen-Nurnberg die Vorlesung „Chemische Zaubertricks” statt. Im Laufe der Jahre und mit dem Generationswechsel hat sich das Gesicht dieser Veranstaltung verandert. Aus der klassischen Experimentalvorlesung ist eine multimediale Show entstanden, die einen bemerkenswerten Erfolg beim Publikum verzeichnen darf und es bis ins Fernsehen geschafft hat. Wir geben hier unsere Erfahrungen und Informationen weiter, die es dem Interessierten moglich machen, selber eine ahnliche Werbeveranstaltung fur die Chemie durchzufuhren. Every year at the start of the winter semester at the Friedrich Alexander University Erlangen-Nurnberg, the lecture „Chemical Magic Tricks” is held. In time and due to generation changes, the nature of this event has changed. From a classical experimental lecture it was transformed into a multi media show, which is very popular among the public and even made its way into television. Our aim with this article is to pass our experience and further information required on to those interested to present such an advertisement event for chemistry.