Millimeter and submillimeter wave studies of the transient molecular species CF2, HO2 and NH2

High resolution millimeter and submillimeter absorption studies have been conducted on the transient species CF2, HO2 and NH2. The detection of the NH2 radical was the first observation of this species in a direct microwave absorption experiment and should facilitate its astronomical detection in dense interstellar clouds. The study of HO2 contained the first detailed analysis of the rotational spectrum of this species and is one of the few such studies ever reported for a nonlinear free radical. It was also the first study of an asymmetric rotor having non-zero electronic angular momentum to be performed in this laboratory. Thirty-seven new millimeter wave transitions have been observed in the transient species CF2. A detailed analysis of the new data and the earlier microwave data have resulted in a more accurate determination of the centrifugal distortion constants. With this analysis it is now possible to predict virtually all of the 662 transitions below 500 GHz arising from thermally populated levels (E < 800 cm-1, J less than or equal to 40) to within 1 MHz. The analysis is also able to predict virtually all of the 662 transitions below 500 GHz arising from thermally populated levels (E < 800 cm-1, J less than or equal to 40) to within 1 MHz. The analysis is also able to predict all transitions below kT (E < 200 cm-1, J less than or equal to 20) to within 50 kHz