Knowledge Bank

Following the "Best Theory + High-resolution Experimental Data" strategy, we have made progress on computing a reliable CO$2$ infrared (IR) line list. A procedure that is similar to the one used for ammonia nderline{\textbf{129}}, 214304 (2008); \textit{J. Chem. Phys.} nderline{\textbf{132}}, \textit{submitted}, (2010).} is adopted to generate a global potential energy surface (PES), including various small corrections such as relativistic correction, basis-set extrapolation and a higher-order correlation correction, which will be followed by refinements using accurate high-resolution laboratory data. The purely \textit{ab initio} PES includes a long-range Morse-potential part and a short-range local interaction part. Finite-Field approximations were adopted in dipole moment calculations using the CCSD(T)/aug-cc-pVQZ level of theory. Quadruple moment terms were computed and included. Exact variational rovibrational calculations on the purely \textit{ab initio} PES and dipole surface have led to our first set of an IR line list. A comparison with HITRAN data will be discussed.