We describe a new experimental facility LEMPUS-2, which provides experimental research in supersonic flows of gases and gas mixtures in the oil-free vacuum. Model experiments in a flow of pure argon in order to verify and test the diagnostic equipment of set-up were performed. Experimental studies of the formation of cluster beams of methane and argon-methane mixtures have been performed to determine the optimal conditions for the formation of intense molecular beams of methane clusters. We obtain an intense molecular beam of methane clusters. It was found that in a supersonic jet of large size pure methane clusters are not diagnosed by the mass spectrum of oligomeric fragments, whereas in mixtures of argon with small admixtures of methane is recorded in the mass spectrum, apparently as oligomers of methane and mixed clusters of argon-methane . It was confirmed that the clustering of methane starts at lower pressures of inhibition than argon and lead to further delay of cluster formation in argon. It is shown that for high intensity methane clusters fluxes should be used specially selected gas mixtures
An experimental study of the formation of mixed van der Waals oxygen-isoprene complexes, generated in an expanding supersonic helium-oxygen-isoprene jet at various stagnation pressures and at diverse oxygen and isoprene concentrations, has been performed. The particularities of applying mass spectrometry to studying clustered isoprene streams in a pulsed mode have been discussed. The composition of small clusters generated in a free supersonic jet has been checked for dependencies upon the initial mixture composition and stagnation pressure. The mechanism of nucleation has been identified for different partial concentrations of impurities in the helium stream. The specific features of the dissociative ionization of van der Waals complexes, consisting of pure isoprene and mixed complexes, have been discussed. The conditions needed for the formation of binary oxygen-isoprene van der Waals complexes have been identified
Modernization of experimental complex LEMPUS-1 was done. Experimental investigations of argon cluster beams formation for ion-cluster surface modification technology were performed. Intensity of cluster beams up to 5*1014 clusters per cm2 per sec with average cluster size about 1300 was obtained. It was found the optimal conditions for cluster beam formation
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