Energy-transfer rates for the

process Na(
2 
+ Na (
2 
Na (
2 
) + Na (
2 
= 17.2 cm
-1have been measured following direct excitation of specific
2 
levels with a pulsed tunable dye laser of 10
-2-Å linewidth and 5-ns duration. The cross sections for the forward and backward reactions at 272°C have been found by Pitre and Krause to be 250 ± 40 and 480 ± 80 Å, respectively.