Mackie Cameron J, Candian Alessandra, Lee Timothy J, Tielens Alexander G G M
Kenneth S. Pitzer Center for Theoretical Chemistry Department of Chemistry, University of California, Berkeley, CA 94720 USA.
Lawrence Berkeley National Laboratory, Chemical Sciences Division, Berkeley, CA 94720 USA.
Theor Chem Acc. 2021;140(9):124. doi: 10.1007/s00214-021-02807-z. Epub 2021 Aug 13.
The profile of the 11.2 μm feature of the infrared (IR) cascade emission spectra of polycyclic aromatic hydrocarbon (PAH) molecules is investigated using a vibrational anharmonic method. Several factors are found to affect the profile including: the energy of the initially absorbed ultraviolet (UV) photon, the density of vibrational states, the anharmonic nature of the vibrational modes, the relative intensities of the vibrational modes, the rotational temperature of the molecule, and blending with nearby features. Each of these factors is explored independently and influence either the red or blue wing of the 11.2 μm feature. The majority impact solely the red wing, with the only factor altering the blue wing being the rotational temperature.
采用振动非谐方法研究了多环芳烃（PAH）分子红外（IR）级联发射光谱中11.2μm特征峰的轮廓。发现有几个因素会影响该轮廓，包括：最初吸收的紫外（UV）光子的能量、振动态密度、振动模式的非谐性质、振动模式的相对强度、分子的转动温度以及与附近特征峰的混合。分别对这些因素进行了研究，它们会影响11.2μm特征峰的红翼或蓝翼。大多数因素仅影响红翼，而唯一改变蓝翼的因素是转动温度。
