A mass spectrometric method for probing surface structure Conference Paper uri icon


  • Coincidence counting mass spectrometry (CCMS) has been used to study the negative and positive cluster ion formation from two inorganic compounds, NaBF4 and αZrP. Coincidence spectra are obtained from conventional mass spectra by collecting only those desorption events that include an ion of interest. Direct comparison of the cluster ion compositions to the stoichiometry and structure of the original solid were made. Negative ions reflect the original solid composition and structure while the positive cluster ions do not. Also, new evidence supports an intact emission for negative cluster ions and a recombination mechanism for positive cluster ions. Changing the crystallinity of the solid affects the negative spectrum, with larger cluster ions observed in the more crystalline samples. No difference is observed with the positive clusters, consistent with a gas phase formation process. In the negative ion mode CCMS can be an effective tool for studying the composition and the nanoscale order of a solid surface. © 1995.

author list (cited authors)

  • Van Stipdonk, M. J., Shapiro, J. B., & Schweikert, E. A.

citation count

  • 4

publication date

  • August 1995

published in