For producing beams of CO 2 with different E i (0.28 eV to 1.7 eV), we employed seeded molecular beams having different concentrations of CO 2 in H 2 ranging from 30% to 0.5%, with the nozzle at 300 K. Higher E i beyond this limit were produced by varying the nozzle temperature up to 850 K. This allowed us to produce CO 2 beams with E i up to 4.6 eV. The backing pressure used in all these measurements was 4 bar.