JMSSJ On-line

JMSSJ On-line, Vol. 44 (1996) No. 2, pp. 229-236

Dynamical Properties of van der Waals Clusters of Amino-acid Tryptophan Molecule		>> Full Text PDF >> References
*Hisayuki YAZAWA,^a) Ryoichi SHISHIDO,^a) Takashi NOZAWA,^a) and Tatsuo ARIKAWA^a)** ^a) Department of Applied Physics, Faculty of Engineering, Tokyo University of Agriculture and Technology (Koganei-shi, Tokyo 184, Japan)*

Formation of van der Waals clusters of amino-acid tryptophan was investigated by means of seeded supersonic expansion combining with laser desorption technique. Stable van der Waals clusters of tryptophan molecules, (Trp)_n up to n=5, were observed in a time-of-flight mass spectrum. No significant difference was observed in the formation of clusters for each enantiomer, i.e., L-, D-, and racemic-tryptophans. Strikingly no dominant van der Waals complexes other than the type of (Trp)_n were observed, though weakly bound van der Waals complexes such as a tryptophan·(rare gas)_n type are commonly seen in an ordinary seeded beam expansion. The dynamical properties of tryptophan dimers, and trimers in a carrier argon gas were measured by the use of a fast optical imaging device.

Key words: Seeded beam, Laser desorption, van der Waals clusters, Tryptophan, Fast optical imaging