Hyperfine interactions in the ground states of titanium monoxide and mononitride

A comparative study of the hyperfine interactions in the X 2Σ+ state of TiN and the X 3Δ state of TiO has been performed. The 48Ti14N(I=1) hyperfine structure was determined from the analysis of 19 components of the N=1--0 and N=2--1 pure rotational transitions recorded using the pump/probe microwave-optical double resonance technique. The 47Ti(I=5/2) hyperfine structure of X 2Σ+ TiN was determined from an analysis of the high resolution optical spectrum of the (0,0) A 2Π3/2--X 2Σ+ band system. The resulting parameters are (in MHz) B(48Ti14N)=18 589.3513(13), D(48Ti14N)=0.026 31(18), γ(48Ti14N)=-52.2070(13), bF(N)=18.480(3), c(N)=0.166(7), eQq0(N)=-1.514(8), CI(N)=0.0137(12), bF(47Ti) =-558.8(11), c(47Ti)=-15(5), and eQq0(47Ti)=62(16). An analysis of the (0,0) band of the B 3Π--X 3Δ system of 47Ti16O produced the X 3Δ hyperfine parameters (in MHz): a(47Ti) =-54.7(21), (bF+2c/3)(47Ti)=-231.6(60), and eQq0(47Ti)=-49(31). An interpretation based upon the predicted nature of the bonding in TiO and TiN is given