Spectroscopy, kinetics and laser effects of photodissociated HgX (X=I, Br and Cl)

Abstract

Spectroscopic and kinetic studies have been made on the mercurous halides HgX (X=Cl, Br, I) photodissociated from HgX2 by an ArF excimer laser excitation at 193 nm. The lifetimes and quenching rates of the HgX B(2 Sigma +12/) state have been determined from the properties of the B to X (2 Sigma +12/) emission. Comparison is made of the spectroscopic behaviour of the three halides and also between photon and electron dissociation. The HgX (B to X) spectra consist of numerous overlapping bands extending from the visible to the UV. The vibrational spectral distribution narrows from Cl, through Br to I and the peak emission wavelength becomes shorter. Characteristics of gain and laser action in HgBr have been investigated.