LASER-INDUCED MOLECULAR DISSOCIATION AND IONIZATION OF POTASSIUM VAPOR

We report a single photon molecular dissociation of potassium vapour, K-2-->(<(h)over bar omega>)K(4s(2)S(1/2)) + K(4P(2)P(1/2,3/2)) and su bsequent excitation and ionization using a Nd:YAG pumped dye laser in conjunction with a thermionic diode detector. The even parity ns S-2(1 /2) and nd D-2(3/2,5/2) Rydberg series resulting from the absorption o f another photon from the same laser pulse by the excited (4p(2)P(1/2, 3/2)) atomic potassium have been detected over the wavelength range 49 4 to 456 nm. Using this excitation and ionization technique, high Rydb erg levels excited from both the 4p fine structure components:4p(2)p(1 /2)-->nd(2)D(3/2)(10 less than or equal to n less than or equal to 24) and ns(2)S(1/2)(10 less than or equal to n less than or equal to 26), 4p(2)P(3/2)-->nd(2)D(3/2,5/2)(8 less than or equal to n less than or equal to 33) and ns(2)S(1/2)(10 less than or equal to n less than or e qual to 29) are observed for the first time. The relative intensities of the Rydberg series attached to these fine structure components demo nstrate that the potassium dimer predominantly to the 4p(2)p(3/2) leve l of the potassium atom.