Because of high temperature, the experimental diagnosis for the combustion intermediates of hydrocarbon fuel is still a great challenge. In this letter, we propose a method to detect qualitatively the combustion intermediates by introducing temperature into the expression of vibrationally resolved electronic spectrum, which is based on the relationship between molecular structure and its spectrum. Using this method, the fine electronic spectra of CO⁺ and N₂⁺ molecules are simulated, and the results reproduce their experimental ones very well, indicating the reliability of this method. Further, the electronic spectra of combustion intermediates C₂N, NO₂, OOH and HCO are predicted and the main vibrational bands are assigned. This work provides theoretical guidance for the qualitative detection of hydrocarbon fuel combustion intermediates under high temperature.

由于高温，对于烃类燃料的燃烧中间体的实验诊断仍然是一个很大的挑战。在这封信中，我们提出了一种基于分子结构与其光谱之间关系的，通过将温度引入振动解析电子光谱表达式中来定性检测燃烧中间体的方法。使用该方法，模拟了CO ⁺和N ₂ ⁺分子的精细电子光谱，结果很好地再现了它们的实验结果，表明了该方法的可靠性。此外，燃烧中间体C ₂ N，NO ₂的电子光谱预测OOH和HCO，并指定主要振动带。这项工作为高温下烃类燃料燃烧中间体的定性检测提供了理论指导。