RATE CONSTANTS FOR REMOVAL BY NOBLE-GASES OF SELECTED ROTATIONAL LEVELS OF METHYLENE B-1(1)(0, 14, 0)

Quenching rate constants for removal by nobel gases have been measured for 0(00), 2(02), 4(04) and 6(06) rotational levels in the B-1(1) (0, 14, 0) state of methylene. For the higher rotational levels the quenc hing is approximately twice as fast as for the lower levels, except fo r the heavy ps xenon, where no significant variation is observed. Appl ication of Parmenter's and multipole force models groups the data arou nd two lines corresponding to lower and higher rotational states. The mechanism of quenching is discussed in terms of the internal perturbat ions affecting the selected rotational states and the perturbations in duced by the atomic collider.