Ab initio study of the PtC molecule. A new assignment of the red bands to the 1 3ΠΩ(Ω=1,0+)–X 1Σ+ transitions

摘要: The electronic excited state spectrum of platinum monocarbide (PtC) was calculated by a multireference configuration interaction (MRCI) method with and without account spin-orbit coupling (SOC). It is shown that the previous assignment red bands (700–880 nm) in PtC should be changed from singlet–singlet transitions A′ 1Π–X 1Σ+ A″ 1Σ+–X  1Σ+ to singlet–triplet 1 3ΠΩ–X 1Σ+ connected two different spin sublevels (Ω=1,0+) lowest triplet 1 3Π state. higher-lying states, A B, supported calculations. corresponds singlet 1 1Π term. first 1Σ+ observed B responsible for very intense UV band (306 nm). This strongly perturbed SOC.