The transition properties of the X¹Σ⁺, C¹Σ^–, D¹Δ, A¹Π, E¹Σ⁺, a³Σ⁺, d³Δ, and b³Π states of silicon monosulphide were investigated using the complete active space self-consistent field method, which was followed by the internally contracted multireference configuration interaction approach. The transition dipole moments were calculated for the dipole–allowed transitions between these singlet states and for all transitions between the X¹Σ⁺, a³Σ⁺, d³Δ, and b³Π states. The radiative lifetimes of the first 16 vibrational levels were 107.6 – 120.5 ns for the A¹Π state and 12.8 – 14.1 ns for the E¹Σ⁺ state. Among these dipole–allowed transitions, the emissions from the A¹Π – X¹Σ⁺ and E¹Σ⁺ – X¹Σ⁺ systems were strong, whereas those from the b³Π – d³Δ system were weak. The radiative lifetimes of the first 16 levels were 4.3 – 9.8, 3.8 – 35.4, 2.2 – 7.9, and 11.9 – 14.5 ms for the a³Σ⁺₁, a³Σ⁺_0–, d³Δ₁, and d³Δ₂ states, respectively. These were 117 – 380, 73 – 581, and 137 – 586 μs for the b³Π₀₊, b³Π₁, and b³Π₂ states, respectively. Among these forbidden transitions, the b³Π₀₊ – X¹Σ⁺₀₊ and b³Π₁ – X¹Σ⁺₀₊ transitions were the strongest. The Franck–Condon factors, Einstein A coefficients, and band origins of all these spontaneous emissions were calculated. The transition properties were compared with the available experimental and theoretical results.

X ¹ Σ ⁺ , C ¹ Σ ^– , D ¹ Δ, A ¹ Π, E ¹ Σ ⁺ , a ³ Σ ⁺ , d ³ Δ, 和 b ³ Π活动空间自洽场方法，其次是内部收缩的多参考配置交互方法。计算了这些单线态之间偶极子允许的跃迁以及 X ¹ Σ ⁺ , a ³ Σ之间的所有跃迁的跃迁偶极矩⁺、d ³ Δ 和 b ³ Π 状态。前 16 个振动能级的辐射寿命对于 A ¹ Π 状态为 107.6 – 120.5 ns，对于 E ¹ Σ ⁺状态为 12.8 – 14.1 ns 。在这些偶极子允许跃迁中，来自 A ¹ Π – X ¹ Σ ⁺和 E ¹ Σ ⁺ – X ¹ Σ ⁺系统的发射很强，而来自 b ³ Π – d ³ Δ 系统的发射很弱。对于 a ³ Σ ，前 16 个能级的辐射寿命分别为 4.3 – 9.8、3.8 – 35.4、2.2 – 7.9 和 11.9 – 14.5 ms⁺ ₁、a ³ Σ ⁺ _0–、d ³ Δ ₁和d ³ Δ ₂状态分别。对于 b ³ Π ₀₊、b ³ Π ₁和 b ³ Π ₂状态，这些分别是 117 – 380、73 – 581 和 137 – 586 μs 。在这些禁止跃迁中，b ³ Π ₀₊ – X ¹ Σ ⁺ ₀₊和 b ³ Π ₁ – X ¹ Σ ⁺ ₀₊过渡是最强的。计算了所有这些自发辐射的 Franck-Condon 因子、Einstein A 系数和波段起源。将过渡特性与可用的实验和理论结果进行了比较。