Low-temperature Rate Constants for Rotational Excitation
نویسندگان
چکیده
The low-temperature rotational (de-) excitation of C3 (X 1 g ) by collisions with He ( S ) is studied using an ab initio potential energy surface (PES). This PES has been calculated using the singleand double-excitation coupledcluster approach with noniterative perturbational treatment of triple excitations [CCSD(T)] and the augmented correlation-consistent triplebasis set (aug-cc-pVTZ) with bond functions. This PES is then incorporated in full close-coupling quantum scattering calculations for collision energies between 0.1 and 50 cm 1 in order to deduce the rate constants for rotational levels of C3 up to j = 10, covering the temperature range 5Y15 K. Subject headingg s: astrochemistry — infrared: ISM — ISM: molecules — molecular data Online material: machine-readable table
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