Combined infrared and ultraviolet-visible spectroscopy matrix-isolated carbon vapor

Abstract
Infrared and UV-visible absorption spectra have been measured on the same sample of matrix-isolated carbon vapor in order to establish correlations between absorption intensities of vibrational and electronic transitions as a function of sample annealing. A high degree of correlation has been found between the IR feature at 1998 cm−1 recently assigned to C8 and a UV absorption feature at about 3100 Å. Thus, for the first time, direct evidence is given for the assignment of one of the unknown UV-visible features of the long-studied matrix-isolated carbon vapor spectrum.