PERTURBATIONS, INTENSITY ANOMALIES, AND LINE BROADENING OF (NAK)-NA-23-K-39 STUDIED BY OPTICAL-OPTICAL DOUBLE-RESONANCE POLARIZATION SPECTROSCOPY

The high resolution spectrum of the (NaK)-Na-23-K-39 molecule in the 33 200-33 340 cm(-1) region is measured by Doppler-free optical-optical double resonance polarization spectroscopy, and the F-1 Delta(upsilon(f) + 4), K-1 Sigma(+)(upsilon(k) + 3), U-1 Pi(upsilon(u) - 1), and W-3 Pi(upsilon(w)) levels are studied. Intensity anomalies between P(J + 1) and R(J - 1)lines are observed for transitions to the K-1 Sigma(+)(upsilon(k) + 3) and U-1 Pi(upsilon(u) - 1) levels, and these are identified as a quantum mechanical interference effect. Energy shifts of the K-1 Sigma(+)(upsilon(k) + 3, J) levels centred at J = 39-40 and the U-1 Pi(upsilon(u) - 1, J) levels centred at J = 30-31 are observed, and these are identified as being caused by an additional interaction with the W-3 Pi state. The line broadenings of the U-1 Pi(upsilon(u) - 1, J) levels centred at J = 35 are observed, and are identified as originating from the predissociation, which leads to two separated atoms K(5p) and Na(4s).