The authors are indebted to Anthony Merer and the members of the high-resolution spectroscopy group at the University of British Columbia for allowing us the use of their Bomem FTIR spectrometer. The invaluable assistance of Chris Chan in recording the spectra and reducing the data is gratefully acknowledged. H. H. acknowledges the support of the Professional Human Resources Development Project;
funded by the government of Indonesia. This research was supported by the Petroleum Research Fund of the American Chemical Society and the Chemical Sciences Division of the U.S. Department of Energy under Contract DE-FG05-86ER13544;