Rotational excitation and de-excitation of C(2)(X 1Sigma(g)+) by para-H(2)(j = 0).

For the van der Waals C(2)(X (1)Sigma(g)(+))-H(2) molecular system, we generated a new ab initio potential energy surface (PES). We mapped this PES at the multireference internally contracted configuration-interaction method including the Davidson correction together with a large diffuse basis set. Then, we incorporated our PES into quantum scattering calculations at the close coupling and infinite order sudden approximation methods to cover collision energies ranging from 0.1 up to 4000 cm(-1). After Boltzmann thermal averaging, rate coefficients for temperatures of up to 1000 K are deduced. Discrepancies between our new rates and those computed previously are noticed. This should induce deviations in astrophysical modeling.