Vibrational Energy Transfer of Some X2CO-type Molecules on Collision with Argon

Vibrational excitation of X2CO-type polyatomic molecules (X=F, Cl, Br, and H) on collision with an argon atom at temperatures 1000–3000 K was treated by the SSH-Tanczos method with a more tractable formula of average vibrational factor. Bending modes are more easily excited than bond-stretching modes in carbonyl halides. Excitation of the carbonyl stretching mode, the most difficult to occur in T–V process, becomes realizable when coupled with other modes to satisfy the near-resonance conditions.