Abstract The transitional characters for eight transition systems of TiO were investigated by using the ab initio calculation. Highly accurate MRCI + Q approach was used to investigate the potential energy curves (PECs) and transition dipole moment curves (TDMCs) with 4221 levels that results are consisted with experimental determinations. Moreover, combining the values of PECs with TDMCs, the Einstein A coefficients, transitional lifetimes, ro-vibrational intensities, absorption oscillator strengths, and frequency-integrated cross sections are calculated including transition bands v′ = 0–6 ← v″ = 0–6. For application in the atmospheres, the absolute intensities and line-shapes of allowed transition systems at different temperature were studied to satisfy some astrophysical applications. The results are also potentially useful for important Astrophysics Data System (ADS) and databases such as HITEMP, NIST. Since the results from many laboratory techniques and our calculations now agree, analyses of TiO based on absorption from allowed transitions are no longer hindered by present determinations.

中文翻译：

---

TiO分子跃迁光谱的理论研究

摘要 采用从头算法研究了TiO 8 个过渡体系的过渡特征。高精度MRCI + Q方法用于研究具有4221个水平的势能曲线（PEC）和跃迁偶极矩曲线（TDMC），结果与实验确定一致。此外，结合 PEC 和 TDMC 的值，可以计算爱因斯坦 A 系数、过渡寿命、旋转振动强度、吸收振荡器强度和频率积分截面，包括过渡带 v' = 0–6 ← v″ = 0– 6. 为了在大气中的应用，研究了不同温度下允许的过渡系统的绝对强度和线形，以满足一些天体物理应用。结果对于重要的天体物理数据系统 (ADS) 和 HITEMP、NIST 等数据库也可能有用。由于许多实验室技术的结果和我们的计算现在一致，基于允许跃迁的吸收的二氧化钛分析不再受当前测定的阻碍。