Laser-induced fluorescence spectrum of argon matrix-isolated dichlorocarbene

Dichlorocarbene has been prepared for spectral investigation by the matrix reaction of alkali metal atoms with carbon tetrachloride at high dilution in argon followed by condensation onto a copper wedge held at 15 K. When these samples were irradiated with laser lines of wavelengths between 5682 and 4545 Å, an intense red emission system peaking around 7000 Å was observed. The spectrum of this emission revealed at least five progressions in the ground state bending and stretching fundamentals. A revised value of the ground state bending mode for CCl₂ was obtained from higher-resolution spectra using more diluted samples and various laser exciting frequencies. Carbon-13 enriched samples confirm the assignments of the bands to progressions in the ground state bending and symmetric stretching modes of CCl₂.