How to photograph a chemical reaction

Kenneth R. Leopold, S. W. Reeve, M. A. Dvorak, W. A. Burns, R. S. Ford, F. J. Lovas, R. D. Suenram

Research output: Chapter in Book/Report/Conference proceedingConference contribution


We report the structural characterization of the gas phase adducts HCN and CH3CN with BF3. Both have symmetric top structures with the nitrogen end of the R-CN toward the boron, reminiscent of the well known dative bond chemistry of BF3 with nitrogen donors. The B-N bond lengths and N-B-F angles, however, are intermediate between those expected for van der Waals or covalent interactions. Moreover, in CH3CN-BF3, where comparison with x-ray crystallographic studies is possible, the gas phase adduct shows a markedly longer bond length and smaller N-B-F angle. We show that in a series of related BF3 and BH3 adducts, the bond length and bond angle can, in fact, be tuned almost continuously between the covalent and van der Waals limits. By analogy with classic crystallographic work by Buergi and Dunitz and coworkers, we discuss how members of such a series can be interpreted as snapshots along a generalized reaction path for the formation of the dative bond. Finally, in the context of such a path, we examine the evolution of other (non-structural) properties of the BF3 adducts as the donor-acceptor bond formation proceeds.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
PublisherPubl by Int Soc for Optical Engineering
Number of pages9
ISBN (Print)0819407844, 9780819407849
StatePublished - 1992
EventOptical Methods for Time- and State-Resolved Chemistry - Los Angeles, CA, USA
Duration: Jan 23 1992Jan 25 1992

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X


OtherOptical Methods for Time- and State-Resolved Chemistry
CityLos Angeles, CA, USA


Dive into the research topics of 'How to photograph a chemical reaction'. Together they form a unique fingerprint.

Cite this