Schweikert Research Group

Selected Publications

S. V. Verkhoturov, M. J. Eller, R. D. Rickman, S. Della-Negra and E. A. Schweikert, Single Impacts of C60 on Solids: Emission of Electrons, Ions and Prospects for Surface Mapping, J. Phys. Chem. C, 2010, 114 (12), 5637–5644 

V. T. Pinnick, S. V. Verkhoturov, L. Kaledin, Y. Bisrat and E. A. Schweikert, Molecular Identification of Individual Nano-Objects, Anal. Chem.,  2009, 81 (18), 7527–7531

S. Rajagopalachary, S. V. Verkhoturov and E. A. Schweikert, Characterization of Individual Ag Nanoparticles and Their Chemical Environment, Anal. Chem., 2009, 81 (3),  1089–1094

V. Pinnick, S. Rajagopalachary, S. V. Verkhoturov, L. Kaledin, E. A. Schweikert, Characterization of Individual Nano-Objects by Secondary Ion Mass Spectrometry, Analyt. Chem., 2008, 80, 9052-9057

C. Guillermier, S. Della Negra, E. A. Schweikert, A. Dunlop, G. Rizza, Emission of Molecular Fragments Synthesized in Hypervelocity Nanoparticle Impacts, Int. J. Mass Spectrom., 2008, 275, 86-90.

Rajagopalachary, S.; Verkhoturov, S.V.; Schweikert, E.A. Examination of Nanoparticles via Single Large Cluster Impacts Nano Letters, in Press, 2008.

 

Current Projects

The accurate identification and quantitation of unknown species at the atto to zeptomole (10-18 to 10-21) level presents formidable challenges. Even more dramatic is their spatiotemporal localization in high performance materials or biological specimens. Our goal is to advance the performance of "chemical vision" to match that of physical microscopy.

Progress towards the limits of chemical analysis and mapping depends on:

Current work funded by the National Science Foundation and the Robert A. Welch Foundation deals with the three themes listed below:

Fundamentals of massive cluster-solid interactions
Studies in progress deal with elucidating mechanisms of surface ionization, measurement od secondary ion (SI) yields, of multiple SI emission, probability distributions of SI emissions, volume of SI emission, characteristics of SI emission.

Methodology and instrument development
Efforts focus on the localization of projectile impacts and the efficient detection/identification of ejecta.

Extreme analysis
The objective is to validate secondary ion mass spectrometry using massive clusters as projectiles for the detection of attomol to zeptomole amounts of analyte and for the characterization of nanoenvironments on surfaces, in membranes and in biological specimens.