A complete energy transfer map for COF2

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Abstract
Fluorescence from the ν1, ν4, ν6, and ν3/ν5 states has been observed following Q-switched CO2 laser excitation of the ν2 C–F stretch mode of COF2. A kinetic model is presented which is consistent with the observed fluorescence lifetimes. Following excitation of the ν2 mode, 2ν2 is rapidly pumped by ladder climbing collisions. The 2ν2 states are collisionlessly coupled to the ν1 mode by Fermi resonance leading to the creation of a steady state between the ν1 and ν2 manifolds within 30 gas kinetic collisions. Subsequently, the ν2 state decays to the ν6 mode in 800 collisions, and also fills the ν4 mode in 2000 gas kinetic collisions. The ν4 level rapidly equilibrates with the near resonant states 2ν3, 2ν5, and ν3+ν5 after about 25 collisions, and these states rapidly decay to the ν3 and ν5 fundamentals in less than or about 100 collisions. The ν6 state relaxes to the ν3/ν5 states, in approximately 190 collisions, while vibration-translation/rotation relaxation of ν3 and ν5 to the ground state occurs on a time scale of 1200 collisions.