Knowledge Bank

The electronic spectrum of $CD3Cl$ has been recorded from 50 000 to 94 000 $cm-1$; energies were determined to $\pm$ 20 $cm-1$ and intensities to $\pm$ 15%. The spectrum is similar in its general features to chat of $CH3Cl$. In particular, two p-Rydberg series are easily discerned which lead to the components of the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}E$ ground state of the $CD3Cl+$ ion, and which are analogous to those observed for $CH3Cl$. The ionization potentials found are 90 730 and 91 350 $\pm$ 20 $cm-1$; these are to be compared to 90 510 and 91 150 $cm-1$ for $CH3Cl$. The photoelectron spectrum of $CD3Cl$ has also been $recorded1$; here the lowest ionization potential, observed corresponds to the upper multiplet component of the $CD3Cl+$ ion. This is exactly analogous to what has been found by other workers for $CH3Cl$. Detailed comparison of the spectra of $CD3Cl$ and $CH3Cl$ has made it possible to distinguish 0-0 Rydberg transitions from vibronic progressions in the complex region above 83 000 $cm-1$. In this way many members of s-Rydberg series have been located and vibrational frequencies in the Rydber states have been determined. The vibronic structure in the lower Rydberg transitions will also be discussed.