Kinetic study of electronically excited tin atoms, Sn(5 1D 2), by atomic absorption spectroscopy

Abstract

The method of spectroscopically studying transient atoms in absorption by time-resolved attenuation of atomic resonance radiation has been applied to electronically excited tin atoms, Sn(5 1D 2). This atomic state was generated by the pulsed irradiation of tin tetramethyl in the presence of excess helium buffer gas and monitored photoelectrically via the resonance transition at λ = 285.06 nm {Sn[5 d( 3F 0 2 ← [5 p 2( 1D 2]}. The resulting technique is found to be highly sensitive and has been used to investigate the collisional behaviour of Sn(5 1D 2) in the presence of the gases He, Xe, H 2, O 2, and SnMe 4, for which quenching rate constants at 300 K are reported. These rate constants are compared with analogous data for other atomic states in Group IV, namely, C(2 p 2 1D 2) and Pb(6 p 2 1D 2), and briefly considered from the viewpoint of spin and orbital symmetry on collision.