The electronic spectrum of ThN over the range 19,600–21,200 cm⁻¹ is remarkably congested, showing at least twenty vibronic bands originating from the ground state zero-point level. Rotationally resolved spectra for eleven of these bands have been examined to probe the underlying reasons for the dense manifold of states. Dispersed fluorescence spectra and fluorescence decay lifetimes were measured to provide addition insights. The experimental measurements were complemented by electronic structure calculations for the low-energy doublet and quartet states. The ab initio calculations yielded a density of excited states that was consistent with the congested spectrum. These states were derived from the formal configurations Th³⁺(6d)N³⁻, Th²⁺(7s²)N²⁻(2p⁵) and Th²⁺(7s6d)N²⁻(2p⁵). The calculations indicated that the rotational and vibrational constants would be characteristic of the electronic configurations. This prediction was not borne out by the experimental data, suggesting that the full range of inter-configurational state interactions were not captured by the computational model.

ThN的电子光谱在19,600–21,200 cm ^-1范围内显着拥塞，显示出至少二十个源自基态零点能级的振动带。已经检查了其中11个波段的旋转分辨光谱，以探究状态密集流形的根本原因。测量了分散的荧光光谱和荧光衰减寿命，以提供更多见解。通过电子结构计算对低能双峰态和四重态进行了实验测量。该从头计算得到激发态，这是与拥挤的频谱一致的密度。这些状态源自形式构型Th ³⁺（6 d）N^3-，Th ²⁺（7 s ²）N ^2-（2 p ⁵）和Th ²⁺（7 s 6 d）N ^2-（2 p ⁵）。计算表明，旋转常数和振动常数将是电子配置的特征。实验数据并未证实这一预测，这表明计算模型并未捕获到所有组态间状态相互作用。